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Sample records for computerized tomography angiography

  1. Computerized tomography and angiography - competing processes in liver diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Wunschik, F.; Luetgemeier, J.; Hoerst, M.

    1981-02-01

    In the diagnostics of liver diseases, computerized tomography is a valuable method. It is particularly superior to angiography in detecting cysts, parasitosis and abscesses. Angiography however is better for known solid tumours regarding differencial diagnosis. Both methods supplement each other in the tumour and bile ducts diagnostics.

  2. 3.0Tesla magnetic resonance angiography (MRA) for comprehensive renal evaluation of living renal donors: pilot study with computerized tomography angiography (CTA) comparison.

    Science.gov (United States)

    Gulati, Mittul; Dermendjian, Harout; Gómez, Ana M; Tan, Nelly; Margolis, Daniel J; Lu, David S; Gritsch, H Albin; Raman, Steven S

    2016-01-01

    Most living related donor (LRD) kidneys are harvested laparoscopically. Renal vascular anatomy helps determine donor suitability for laparoscopic nephrectomy. Computed tomography angiography (CTA) is the current gold standard for preoperative imaging; magnetic resonance angiography (MRA) offers advantages including lack of ionizing radiation and lower incidence of contrast reactions. We evaluated 3.0T MRA for assessing renal anatomy of LRDs. Thirty consecutive LRDs underwent CTA followed by 3.0T MRA. Data points included number and branching of vessels, incidental findings, and urothelial opacification. Studies were individually evaluated by three readers blinded to patient data. Studies were reevaluated in consensus with discrepancies revealed, and final consensus results were labeled "truth". Compared with consensus "truth", both computed tomography (CT) and magnetic resonance imaging were highly accurate for assessment of arterial and venous anatomy, although CT was superior for detection of late venous confluence as well as detection of renal stones. Both modalities were comparable in opacification of lower ureters and bladder; MRA underperformed CTA for opacification of upper urinary tracts. 3.0T MRA enabled excellent detection of comprehensive renal anatomy compared to CTA in LRDs. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Computerized ionospheric tomography

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    Austen, J.R.; Raymund, T.D.; Klobuchar, J.A.; Stalker, J.; Liu, C.H.

    1990-05-03

    In this paper the background of computerized tomography (CT) and its application to the ionosphere is reviewed. CT techniques, using only total electron content (TEC) data, can be used to reconstruct a two-dimensional image of the electron density in the ionosphere. The limitations of this technique are discussed and examples showing the limitations and capabilities are presented. Simulation results for two applications are presented: imaging the high latitude trough, and the correction of tracking radar range rate errors. Some possible extensions of the technique are presented.

  4. Can carotid stenosis be operated without arteriography? Contribution of magnetic resonance and helical computerized tomography angiography; Peut-on operer une stenose carotidienne sans arteriographie? Apport de l`angioMR et/ou de l`angioscanner helicoidal

    Energy Technology Data Exchange (ETDEWEB)

    Auffrau-Calvier, E.; Kersaint-Gilly, A. de; Desal, H.A.; Viarouge, M.P.; Havet, T. [Hopital Laennec, 44 - Nantes (France)

    1996-09-01

    The aim of this work is to ascertain the role of the magnetic resonance angiography (MRA) and to compare it with the Doppler effect, the X-ray angiography and the new method of helical computerized tomography. Seventy one carotid bifurcations in 37 patients with suspected cerebral vascular events has been evaluated with the MRA and digitalized angiography, the reference method. The obtained data corroborate the good results proposed by other authors reporting in the literature and allow to propose this examination as a new means of investigating carotid bifurcations. Work with the helical computerized tomography appears to be promising too but there are few reported series. Therefore, there appears to be two interesting points: the reliability of distinguishing between very severe stenosis and occlusion, and the fine-tuned analysis of the plaque with detection of ulcerations. When a consistent approach is used to the evaluation of the carotid bifurcation, the Willis circle and the cerebral parenchyma, the MRA can complete the Doppler echo data and the preoperative arteriography can only be used in patients when the MRA and the Doppler echo results disagree. (authors)

  5. Application of 3-Dimensional Computerized Tomography Angiography for Defining Cavernous Sinus Aneurysms and Intradural Aneurysms Involving the Internal Carotid Artery Around the Anterior Clinoid Process.

    Science.gov (United States)

    Cheng, Quan; Huang, Chun-Bo; Wang, Jun-Yu; Jiang, Bing; Zhang, Long-Bo; Zeng, Ming; Chen, Yuan-Bing; Zhang, Hong-Fu; Chen, Feng-Hua

    2017-10-01

    This study aimed to investigate the application of 3-dimensional computed tomography angiography (3D-CTA) for defining cavernous sinus aneurysms and intradural aneurysms involving the internal carotid artery around the anterior clinoid process. Results from 42 patients with an aneurysm of the internal carotid artery around the anterior clinoid process who underwent 3D-CTA were reviewed and compared with those of observed clinical operations. Among the 42 patients, there was a total of 45 aneurysms of the internal carotid artery around the anterior clinoid process. After surgery, 33 of the 45 aneurysms were confirmed as intradural aneurysms, and the other 12 were confirmed as aneurysms in the cavernous sinus. 3D-CTA imaging of the medial sagittal plane showed that 31 out of 31 (100%) intradural aneurysms of the internal carotid artery were above the virtual line between the inferior border of the anterior clinoid process and the tuberculum sellae, and 12 out of 14 (86%) cavernous sinus aneurysms were below the virtual line (P cavernous sinus aneurysms from intradural aneurysms involving the internal carotid artery around the anterior clinoid process. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Technical innovation: Multidimensional computerized software enabled subtraction computed tomographic angiography.

    Science.gov (United States)

    Bhatia, Mona; Rosset, Antoine; Platon, Alexandra; Didier, Dominique; Becker, Christoph D; Poletti, Pierre-Alexandre

    2010-01-01

    Computed tomographic angiography (CTA) is a frequent noninvasive alternative to digital subtraction angiography. We previously reported the development of a new subtraction software to overcome limitations of adjacent bone and calcification in CT angiographic subtraction. Our aim was to further develop and improve this fast and automated computerized software, universally available for free use and compatible with most CT scanners, thus enabling better delineation of vascular structures, artifact reduction, and shorter reading times with potential clinical benefits. This computer-based free software will be available as an open source in the next release of OsiriX at the Web site http://www.osirix-viewer.com.

  7. Multi-detector computerized tomography angiography for evaluation of acute chest pain--a meta analysis and systematic review of literature.

    Science.gov (United States)

    Athappan, Ganesh; Habib, Muzzmal; Ponniah, Thirumalaikolundusubramanian; Jeyaseelan, Lakshmanan

    2010-05-28

    Evaluation of pain localized to the chest in the emergency room is, challenging, time-consuming, costly, and often inconclusive. Available research, though limited, suggests a role for MDCTA in the evaluation of patients with acute chest pain of low to intermediate risk, for identifying and excluding ACSs during the initial emergency department evaluation. Accordingly, our aim was to conduct a meta-analysis to assess the diagnostic accuracy of MDCTA in this setting. We included all studies that compared MDCTA with either coronary angiography or standard of care for early and accurate triage of patients presenting with acute chest pain. Published studies were identified by searches of the Pubmed, Ovid and Google scholar databases as well as hand searches of selected references. Data were extracted independently by two reviewers. Included studies were evaluated for heterogeneity. Meta-analysis was performed at patient level using a random-effects model. 16 studies totaling 1119 patients were included in the current meta-analysis: one randomized trial, one retrospective analysis and fourteen prospective cohort studies. Pooled DOR was 190.80 (95%CI, 102.94-353.65). The pooled sensitivity and specificity were 0.96 (95%CI, 0.93-0.98) and 0.92(95%CI, 0.89-0.94) respectively. The pooled NLR and PLR were 0.09 (95%CI, 0.06-0.14) and 10.12 (95%CI, 6.73-15.22). MDCTA has an excellent diagnostic accuracy in detection of significant coronary artery stenosis in patients with acute chest pain. This diagnostic accuracy of MDCTA has a potential for rapid triage of patients in the ED, with acute chest pain of low to intermediate risk of acute coronary syndrome, to rule out significant epicardial stenosis as the etiology of chest pain. Copyright 2008 Elsevier Ireland Ltd. All rights reserved.

  8. Multislice computed tomography coronary angiography

    NARCIS (Netherlands)

    F. Cademartiri (Filippo)

    2005-01-01

    markdownabstract__Abstract__ Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield

  9. [Recurrence of rectal cancer in computerized tomography].

    Science.gov (United States)

    Kuckein, D

    1981-04-01

    In contrast to conventional methods of x-ray diagnosis, recurrence of a rectum carcinoma may be visualized directly by means of computerized tomography. CT criteria of a tumor relapse are discussed. Based on own cases, it is shown that the method is usually employed too late. CT as follow-up examination should be used as a routine procedure in order to establish an early diagnosis of tumor recurrence.

  10. Computed tomography and angiography in pancreatic apudomas and cystadenomas

    Energy Technology Data Exchange (ETDEWEB)

    Kolmannskog, F.; Schrumpf, E.; Valnes, K. (Rikshospitalet, Oslo (Norway))

    1982-01-01

    During a 4-year period 17 patients with pancreatic apudoma and 3 patients with cystadenoma of the pancreas were admitted to this hospital. Computed tomography correctly located 3 of 4 insulinomas examined, while angiography revealed 4 of 8, which indicates that CT may replace angiography as the primary examination of these tumors, and possibly also other types of apudomas. When CT fails angiography may demonstrate a pancreatic tumor, suggesting angiography as a supplementary examination. In cystadenoma sufficient information was obtained at CT.

  11. Optical Coherence Tomography Angiography of Chorioretinal Diseases.

    Science.gov (United States)

    Novais, Eduardo A; Roisman, Luiz; de Oliveira, Paulo Ricardo Chaves; Louzada, Ricardo N; Cole, Emily D; Lane, Mark; Filho, Marco Bonini; Romano, André; de Oliveira Dias, João Rafael; Regatieri, Caio V; Chow, David; Belfort, Rubens; Rosenfeld, Philip; Waheed, Nadia K; Ferrara, Daniela; Duker, Jay S

    2016-09-01

    Fluorescein angiography (FA) and indocyanine green angiography (ICGA) have been the gold standard for the evaluation of retinal and choroidal vasculature in the last three decades and have revolutionized the diagnosis of retinal and choroidal vascular diseases. The advantage of these imaging modalities lies in their ability to document retinal and choroidal vasculature through the dynamic assessment of contrast transit over time in the intravascular and extravascular spaces. However, disadvantages include the absence of depth resolution, blurring of details by contrast leakage, and the inability to selectively evaluate different levels of the retinal and choroidal microvasculature. In addition, these angiographic methods require intravenous dye, which may cause adverse reactions such as nausea, vomiting, and rarely, anaphylaxis. Optical coherence tomography angiography (OCTA) is a noninvasive imaging technique that, in contrast to dye-based angiography, is faster and depth-resolved, allowing in some cases for more precise evaluation of the vascular plexuses of the retina and choroid. The method has been demonstrated in the assessment of various vascular diseases such as venous occlusions, diabetic retinopathy, macular neovascularization, and others. Limitations of this imaging modality include a small registered field of view and the inability to visualize leakage and dye transit over time. It is also subject to a variety of artifacts, including those generated by blinking and eye movement during image acquisition. However, more than an alternative for FA and ICGA, OCTA is bringing new insights to our understanding of retinal and choroidal vascular structure and is changing fundamental paradigms in the clinical management of pathologic conditions. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:848-861.]. Copyright 2016, SLACK Incorporated.

  12. Computed tomography coronary angiography in patients with acute myocardial infarction and normal invasive coronary angiography

    NARCIS (Netherlands)

    Panayi, Georgios; Wieringa, Wouter G.; Alfredsson, Joakim; Carlsson, Jorg; Karlsson, Jan-Erik; Persson, Anders; Engvall, Jan; Pundziute, Gabija; Swahn, Eva

    2016-01-01

    Background: Three to five percent of patients with acute myocardial infarction (AMI) have normal coronary arteries on invasive coronary angiography (ICA). The aim of this study was to assess the presence and characteristics of atherosclerotic plaques on computed tomography coronary angiography

  13. Significance of computerized tomography and nasal cytology in the ...

    African Journals Online (AJOL)

    Significance of computerized tomography and nasal cytology in the diagnosis of rhinosinusitis among asthmatic children. Karima Abdel Khalik, Laila AG Hegazy, Hassan A Wahba, Laila A Abdurrahman, Sahar SA Zaki ...

  14. Radation distribution in head & thorax computerized tomography

    Directory of Open Access Journals (Sweden)

    Mohammad Mahdavi

    2014-05-01

    Full Text Available Background: Determination of the exposure levels in the computerized tomography (CT practices is necessary to define the respected national reference levels, quality control of CT centers and the risk assessment for radiation induced cancers. Material and Methods: On the basis of this necessity, the radiation exposure distribution due to common CT practices has been investigated at Razi Hospital CT center in Rasht using tissue-equivalent phantoms and the thermoluminescent dosimeters (TLD. The Head and Thorax phantoms were used with the standard dimensions incorporating holes at the center and edges for TLD placement. Dosimetry was carried out using LiF Mg, Cu, P small chips due to their relatively tissue equivalence, high sensitivity convenient annealing procedure and the non-complex glow curve. Results: Results showed that CTDI for Head is 52.85 mGy and for Body is 68.15mGy. CTDLW for Head is 13.67 mGy and for Body is 16.94mGy . Conclusion: In comparison with other radiographical procedures, patient absorbed doses in CT imaging are usually very high. Content of dose is increased by increase of mAs.

  15. Study on forefoot by computerized tomography

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    Machida, Eiichi (Nihon Univ., Tokyo. School of Medicine)

    1983-10-01

    Computerized tomography (CT) was used to study coronary sections of the forefoot in both normal and abnormal human feet. CT images of the transverse arches at the metatarsal head, middle and base of the shaft were classified into five patterns. In the pattern most commonly found in normal feet, the second metatarsus appeared elevated above the other metatarsal bones at all points, and there was a gradual and even reduction in elevation from the second to the fifth metatarsal. In cases of hallux valgus, however, a variety of deformities were noted in the arc of the second to fifth metatarsals, particularly at the head. The rotation of the first metatarsus and shift of the sesamoids were measured from CT images at the head of the first metatarsus. In hallux valgus, both the rotation and the sesamoid shift appeared to have a wider angle than in the case of normal feet. In normal feet, the differences between the rotation of the first metatarsus and shift of the sesamoids were relatively small, whereas in hallux valgus there was a much greater degree of variation. Furthermore, while normal feet the variation in rotation of the first metatarsus and sesamoid shift both tended to be either great or small, in hallux valgus a large degree of sesamoid shift was sometimes found in combination with a small degree of rotation of the first metatarsus.

  16. 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...... angiography (CCTA) in detailed image quality. Material and Methods A total of 160 CCTA were reconstructed as follows: 55 scans with filtered back projection (FBP) (650 mA), 51 scans (455 mA) with 30% ASIR (ASIR30), and 54 scans (295 mA) with 60% ASIR (ASIR60). For each reconstruction, subjective image quality...... was assessed by five independent certified cardiologists using a visual grading analysis (VGA) with five predefined image quality criteria consisting of a 5-point scale. Objective measures were contrast, noise, and contrast-to-noise ratio (CNR). Results The CTDIvol resulted in 10.3 mGy, 7.4 mGy, and 4.6 m...

  17. OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN PATIENTS WITH RETINITIS PIGMENTOSA.

    Science.gov (United States)

    Alnawaiseh, Maged; Schubert, Friederike; Heiduschka, Peter; Eter, Nicole

    2017-10-24

    To evaluate the correlation between the flow density measured by optical coherence tomography angiography and functional parameters in patients with retinitis pigmentosa. Twenty eyes of 20 patients with retinitis pigmentosa and 21 eyes of 21 healthy subjects were prospectively included in this study. Optical coherence tomography angiography was performed using RTVue XR Avanti with AngioVue (Optovue Inc). The macula was imaged with a 6 × 6-mm scan, whereas for the optic nerve head a 4.5 × 4.5-mm scan was taken. Visual acuity, visual field parameters (mean deviation and visual field index), full-field electroretinography, and multifocal electroretinography were tested for correlation with flow density data. The flow density (whole en face) in the superficial/deep retinal OCT angiograms and in the optical coherence tomography angiography of the optic nerve head was significantly lower in the retinitis pigmentosa group when compared with the control group (P retinal OCT angiogram (fovea) correlated significantly with the visual acuity (rSpearman = -0.77, P retinitis pigmentosa show a decreased macular and optic nerve head perfusion compared with healthy subjects. The flow density measured using optical coherence tomography angiography correlated with subjective and objective functional parameters.

  18. [Evaluation of diabetic microangiopathy using optical coherence tomography angiography].

    Science.gov (United States)

    Czakó, Cecília; Sándor, Gábor László; Ecsedy, Mónika; Szepessy, Zsuzsanna; Borbándy, Ágnes; Resch, Miklós; Papp, András; Récsán, Zsuzsa; Horváth, Hajnalka; Nagy, Zoltán Zsolt; Kovács, Illés

    2018-02-01

    Optical coherence tomography angiography is a non-invasive imaging technique that is able to visualize the different retinal vascular layers using motion contrast to detect blood flow without intravenous dye injection. This method might help to assess microangiopathy in diabetic retinopathy during screening and follow-up. To quantify retinal microvasculature alterations in both eyes of diabetic patients in relation to systemic risk factors using optical coherence tomography angiography. Both eyes of 36 diabetic patients and 45 individuals without diabetes were examined. Duration of diabetes, insulin therapy, blood pressure, HbA 1c , dyslipidemia, axial length and the presence of diabetic retinopathy were recorded. Retinal vessel density was measured by optical coherence tomography angiography. The effect of risk factors on vessel density and between-eye asymmetry was assessed using multivariable regression analysis. Vessel density was significantly lower and between-eye difference was significantly higher in diabetic patients compared to controls (pdiabetes duration (pdiabetic retinopathy compared to control subjects (pdiabetes compared to healthy subjects. By using optical coherence tomography angiography, the detection of these microvascular alterations is possible before clinically detectable diabetic retinopathy and might serve as a useful tool in both screening and timing of treatment. Orv Hetil. 2018; 159(8): 320-326.

  19. Morphological analysis of the vestibular aqueduct by computerized tomography images

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    Marques, Sergio Ricardo [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil)]. E-mail: sergioanat.morf@epm.br; Smith, Ricardo Luiz [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Isotani, Sadao [Institute of Physics, University of Sao Paulo, Sao Paulo (Brazil); Alonso, Luis Garcia [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Anadao, Carlos Augusto [Otorhinolaryngology Department, Sao Paulo Federal University-Paulista Medical School, Sao Paulo (Brazil); Prates, Jose Carlos [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Lederman, Henrique Manoel [Image Diagnosis Department, Sao Paulo Federal University-Paulista Medical School, Sao Paulo (Brazil)

    2007-01-15

    Objective: In the last two decades, advances in the computerized tomography (CT) field revise the internal and medium ear evaluation. Therefore, the aim of this study is to analyze the morphology and morphometric aspects of the vestibular aqueduct on the basis of computerized tomography images (CTI). Material and method: Computerized tomography images of vestibular aqueducts were acquired from patients (n = 110) with an age range of 1-92 years. Thereafter, from the vestibular aqueducts images a morphometric analysis was performed. Through a computerized image processing system, the vestibular aqueduct measurements comprised of its area, external opening, length and the distance from the vestibular aqueduct to the internal acoustic meatus. Results: The morphology of the vestibular aqueduct may be funnel-shaped, filiform or tubular and the respective proportions were found to be at 44%, 33% and 22% in children and 21.7%, 53.3% and 25% in adults. The morphometric data showed to be of 4.86 mm{sup 2} of area, 2.24 mm of the external opening, 4.73 mm of length and 11.88 mm of the distance from the vestibular aqueduct to the internal acoustic meatus, in children, and in adults it was of 4.93 mm{sup 2}, 2.09 mm, 4.44 mm, and 11.35 mm, respectively. Conclusions: Computerized tomography showed that the vestibular aqueduct presents high morphological variability. The morphometric analysis showed that the differences found between groups of children and adults or between groups of both genders were not statistically significant.

  20. Functional control of the renal transplant via sequential computerized tomography

    Energy Technology Data Exchange (ETDEWEB)

    Treugut, H.; Nyman, U.; Hildell, J.; Molde, A.

    1981-08-01

    The enhancement of cortex medulla and arteria iliaca can be visualized separately, evaluated densitometrically and represented graphically by means of sequential computerized tomography of the renal transplant following intravenous contrast medium bolus injection. Since this enhancement performance is mainly dependent on perfusion, it is possible to determine the perfusion value of individual measurement areas. For example, a cortical defective perfusion, as is known in rejection, becomes evident as a flattening-out of the initial rise of cortex enhancement and can be distinguished from the largely normal type of curve obtained in acute tubular necrosis (ATN). The angiographically known prolonged 'wash-out time' in rejection corresponds to a long-lasting corticomedullary density gradient. Despite restricted informative value because of the relatively small number of patients, it appears that sequential computerized tomography enables differentiation of postoperative anuria.

  1. Computerized tomography in the diagnosis and treatment of orbital cellulitis

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, M.; Lifshitz, T.

    1988-05-01

    Acute sinusitis remains the major cause of orbital cellulitis in children, despite the extensive use of antibiotics. Staging of orbital cellulitis on the basis of clinical signs is difficult but is easily achieved by computerized tomography. The CT findings in a series of 9 children with orbital cellulitis in different stages are reported. The information obtained by CT contributes to the selection of an adequate surgical approach, if a therapeutic trial with antibiotics fails.

  2. Positive predictive value of computed tomography coronary angiography in clinical practice

    NARCIS (Netherlands)

    Groothuis, J.G.J.; Beek, A.M.; Meijerink, M.R.; Brinckman, S.L.; Heijmans, M.W.; van Kuijk, C.; van Rossum, A.C.

    2012-01-01

    Background: Several studies have investigated the diagnostic performance of computed tomography coronary angiography (CTCA) for the detection of significant coronary artery disease (CAD). These studies were performed in patients that were already referred for invasive coronary angiography (ICA) and

  3. Diagnosing coronary artery disease after a positive coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Nissen, L; Winther, S; Westra, J

    2018-01-01

    Aims: Perfusion scans after coronary computed tomography angiography (CCTA) in patients with suspected coronary artery disease (CAD) may reduce unnecessary invasive coronary angiographies (ICAs). However, the diagnostic accuracy of perfusion scans after primary CCTA is unknown. The aim...

  4. Catheter Angiography

    Medline Plus

    Full Text Available ... Angiography 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 ...

  5. Patients' Views of Cardiac Computed Tomography Angiography Compared With Conventional Coronary Angiography

    DEFF Research Database (Denmark)

    Sandgaard, Niels C F; Diederichsen, Axel Cosmus Pyndt; Petersen, Henrik

    2012-01-01

    PURPOSE: Coronary computed tomography angiography (CTA) has proven to be useful for noninvasive examination in patients with intermediate risk of coronary artery disease. However, data addressing patients' views of this relatively new diagnostic modality are sparse. MATERIALS AND METHODS: For com......PURPOSE: Coronary computed tomography angiography (CTA) has proven to be useful for noninvasive examination in patients with intermediate risk of coronary artery disease. However, data addressing patients' views of this relatively new diagnostic modality are sparse. MATERIALS AND METHODS......: For comparison of CTA and invasive coronary angiography (CA), a total of 127 patients referred for CA for the suspicion of coronary artery disease were included in the study. Three months later the patients received a simple structured questionnaire addressing their views and preferences with regard to CTA...... versus CA. RESULTS: A total of 122 of 127 patients agreed to participate in the study. Pain or bleeding at the puncture site the day after the procedure was significantly more prevalent after CA than CTA (pain, 53% vs 2%; bleeding, 75% vs 22%). More patients had to stay home from work after CA...

  6. Computed tomography angiography in patients with active gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Fatima Regina Silva; D' Ippolito, Giuseppe, E-mail: fatima.rsreis@gmail.com [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina; Cardia, P.P. [Hospital Vera Cruz, Campinas, SP (Brazil)

    2015-11-15

    Gastrointestinal bleeding represents a common medical emergency, with considerable morbidity and mortality rates, and a prompt diagnosis is essential for a better prognosis. In such a context, endoscopy is the main diagnostic tool; however, in cases where the gastrointestinal hemorrhage is massive, the exact bleeding site might go undetected. In addition, a trained professional is not always present to perform the procedure. In an emergency setting, optical colonoscopy presents limitations connected with the absence of bowel preparation, so most of the small bowel cannot be assessed. Scintigraphy cannot accurately demonstrate the anatomic location of the bleeding and is not available at emergency settings. The use of capsule endoscopy is inappropriate in the acute setting, particularly in the emergency department at night, and is a highly expensive method. Digital angiography, despite its high sensitivity, is invasive, presents catheterization-related risks, in addition to its low availability at emergency settings. On the other hand, computed tomography angiography is fast, widely available and minimally invasive, emerging as a promising method in the diagnostic algorithm of these patients, being capable of determining the location and cause of bleeding with high accuracy. Based on a critical literature review and on their own experience, the authors propose a computed tomography angiography protocol to assess the patient with gastrointestinal bleeding. (author)

  7. In vivo coronary lesion differentiation with computed tomography angiography and intravascular ultrasound as compared to optical coherence tomography

    NARCIS (Netherlands)

    Wieringa, Wouter G.; Lexis, Chris P. H.; Lipsic, Erik; van der Werf, Hindrik W.; Burgerhof, Johannes G. M.; Hagens, Vincent E.; Bartels, G. Louis; Broersen, Alexander; Schurer, Remco A. J.; Tan, Eng-Shiong; van der Harst, Pim; van den Heuvel, Ad F. M.; Willems, Tineke P.; Pundziute, Gabija

    Background: In vitro studies have shown the feasibility of coronary lesion grading with computed tomography angiography (CTA), intravascular ultrasound (IVUS) and optical coherence tomography (OCT) as compared to histology, whereas OCT had the highest discriminatory capacity. Objective: We

  8. A new method for tibial torsion measurement by computerized tomography.

    Science.gov (United States)

    Madadi, Firooz; Madadi, Firoozeh; Maleki, Arash; Shamie, Arya Nick; Washington, Eleby Rudolph; Yazdanshenas, Hamed

    2016-03-01

    Computerized tomography (CT) is the gold standard technique for tibial torsion assessment. This study compared two methods of tibial torsion assessment and proposed a new method, which could be of value in cases of abnormal fibular changes. The CT-scanograms of 60 participants were assessed by using two different techniques, differed in determination of the distal tibial axis. The interobserver reliability was 0.861 and 0.863 in the first and second methods, respectively. The intraobserver reliability in both measurement methods was 0.868. We proposed a reliable method, independent of the fibular midpoint, in assessment of tibial torsion by CT.

  9. Computerized tomography used as a routine procedure at postmortem investigations

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2009-01-01

    This is a prospective investigation of a consecutive series of 250 deceased individuals who were computerized tomography (CT)-scanned and autopsied. In 13% of patients, important findings at the CT-scanning were not found at the autopsy, and in 48% of patients, important autopsy findings were not...... and allows fractures and inner organs to be seen "in situ." CT provides documentation in digital form - easily stored - permits review by others and provides pictures that may be more suitable for presentation in court than autopsy photos....

  10. Two-Phase Flow Regime Identification by Ultrasonic Computerized Tomography

    Directory of Open Access Journals (Sweden)

    Mohd Hafiz FAZALUL RAHIMAN

    2010-05-01

    Full Text Available This paper describes the development of ultrasonic computerized tomography for identifying the liquid and gas flow regimes. The work reported in this paper demonstrates image reconstruction techniques applied to an experimental vessel using non-invasive technique. The investigations were based on the transmission and the reception of ultrasonic sensors that were mounted circularly on the surface of an experimental vessel. The algorithms used to reconstruct the concentration profile for two-phase flow using fan-shaped beam scanning geometry were also presented.

  11. Three-dimensional computed tomography angiography of coronary artery bypass graft with electron beam tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Toshiko; Yamauchi, Tatsuo; Kanauchi, Tetsu; Konno, Miyuki; Imai, Kamon; Suwa, Jiro; Onoguchi, Katsuhisa; Hashimoto, Kazuhiro; Horie, Toshinobu [Saitama Cardiovascular and Respiratory Center, Konan (Japan)

    2001-10-01

    Assessment of coronary artery bypass graft patency by three-dimensional reconstructed computed tomography angiography (3D-CTA) derived from electrocardiography-gated contrast-enhanced electron beam tomography (EBT) was evaluated. Thirty-nine patients with 99 grafts (45 arterial grafts and 54 venous grafts) underwent 3D-CTA and selective coronary angiography within a 3-week interval. 3D-CTA images of the coronary bypass grafts were compared with the coronary angiography images used as the control. 3D-CTA defined 42 of 44 arterial grafts as patent (sensitivity: 95%), all 47 venous grafts as patent (sensitivity: 100%) and all 7 venous grafts as occlusive (specificity: 100%). The overall sensitivity and specificity were 98% and 88%, respectively. 3D-CTA is an useful noninvasive technique with adequate sensitivity and specificity to assess coronary artery bypass graft patency. (author)

  12. 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.

  13. Analysis of enlarged images using time-of-flight magnetic resonance angiography, computed tomography, and conventional angiography.

    Science.gov (United States)

    Heo, Yeong-Cheol; Lee, Hae-Kag; Yang, Han-Jun; Cho, Jae-Hwan

    2014-12-01

    This study aimed to assess the accuracy of time-of-flight magnetic resonance angiography, computed tomography, and conventional angiography in depicting the actual length of the blood vessels. Three-dimensional time-of-flight magnetic resonance angiography and computed tomography angiography were performed using a flow phantom model that was 2.11 mm in diameter and had a total area of 0.26 cm(2). After this, volume rendering technique and the maximum intensity projection method as well as two-dimensional digital subtraction angiography and three-dimensional rotational angiography based on conventional angiography were conducted. For three-dimensional time-of-flight magnetic resonance angiography, 8 channel sensitivity encoding (SENSE) head coil for the 3.0 Tesla equipment was used. Fluid was added to the normal saline solution at various rates, such as 11.4, 20.0, 31.4, 40.0, 51.5, 60.0, 71.5, 80.1, 91.5, and 100.1 cm/s using an automatic contrast media injector. Each image was thoroughly examined. After reconstructing the image using the maximum intensity projection method, the length of the conduit in the center of the coronal plane was measured 30 times. After performing computed tomography angiography with the 64-channel CT scanner and 16-channel CT scanner, the images were sent to TeraRecon. Then, the length of the conduit in the center of the coronal plane of each image was measured 30 times after reconstructing the images using volume rendering and maximum intensity projection techniques. For conventional angiography, three-dimensional rotational angiography and two-dimensional digital subtraction angiography were used. Images obtained by three-dimensional rotational angiography were reconstructed and enhanced by 33, 50, and 100 % in the 128 Matrix and the 256 Matrix, respectively on the Xtra Vision workstation. The maximum intensity projection was used for the reconstruction, and the length of the conduit was measured 30 times in the center of the coronal

  14. Computed tomography angiography and magnetic resonance angiography imaging of the mesenteric vasculature.

    Science.gov (United States)

    Hagspiel, Klaus D; Flors, Lucia; Hanley, Michael; Norton, Patrick T

    2015-03-01

    Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are highly accurate cross-sectional vascular imaging modalities that have almost completely replaced diagnostic catheter angiography for the evaluation of the mesenteric vasculature. CTA is the technique of choice when evaluating patients with suspected mesenteric ischemia; it permits to differentiate between occlusive and nonocclusive etiologies, to evaluate indirect signs of bowel ischemia, and in some instances, to provide alternative diagnoses. MRA has the advantage of not using ionizing radiation and iodinated contrast agents and can be appropriate in the nonacute setting. Both CTA and MRA are suitable for the assessment of patients with suspected chronic mesenteric ischemia, allowing to evaluate the degree of atherosclerotic steno-occlusive disease and the existence of collateral circulation, as well as other nonatherosclerotic vascular pathologies such as fibromuscular dysplasia and median arcuate ligament syndrome. CTA provides excellent depiction of visceral aneurysms and has an important role to plan therapy for both occlusive and aneurysmal diseases and in the follow-up of patients after open or endovascular mesenteric revascularization procedures. This article provides an introduction to the CTA and MRA imaging protocol to study the mesenteric vasculature, the imaging findings in patients presenting with acute and chronic mesenteric ischemia and visceral aneurysms, and the value of these imaging techniques for therapy planning and follow-up. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Findings of psychopathology and computerized tomography in neuropsychiatric diseases

    Energy Technology Data Exchange (ETDEWEB)

    Gross, G.; Huber, G.; Schuettler, R.

    1982-08-01

    1978-1980 we examined 451 patients of the Psychiatric University Clinic of Bonn by computerized tomography. From 260 patients with characterized diseases of the brain and brain damages, 78 patients had neuropsychiatric diseases of old age, i.e. cerebro-vascular processes (average age of 63.7 years) and 9 patients had primary degenerative processes of the brain (average age of 62.1 years). Patients with diseases of the cerebral vessels showed irreversible psychopathological syndromes in 87%. The rate of pathological findings in CT increases in relation to degree of severity of the chronic (irreversible) organic psychosyndromes from 76% in pseudoneurasthenics syndromes to 93% in patients with organic changes of personality and to 100% in patients with dementia. The ambiguity of the conception of the multi-infarct-dementia is discussed. Only 19% of the sample with irreversible psychopathological changes showed localized neurological deficits and infarctions in CT, but none of them more than one. In all patients with dementia a cortical atrophy was found. There is a significant positive correlation between cerebral atrophy in CT and irreversible organic psychosyndrome. These findings with computerized tomography demonstrate in accordance with earlier pneumoencephalographic findings that distinct types of irreversible psychosyndromes can be correlated to distinct types of cerebral atrophy. But these statistical correlations between the degree of the severity of the loss of psychic functions and the reduction of cerebral tissue are not necessarily valid for any single case.

  16. Application of computerized tomography to the investigation of ionospheric structures

    Energy Technology Data Exchange (ETDEWEB)

    Raymund, T.D.; Austen, J.R.; Franke, S.J.; Liu, C.H.; Klobuchar, J.A.

    1990-10-01

    Ionospheric total electron content (TEC) measurements, obtained simultaneously at several locations, can be processed using computerized tomography (CT) algorithms to obtain two-dimensional images of ionospheric electron density. Using TEC data computerized ionospheric tomography (CIT) reconstructs an image of the electron density structures in a vertical slice above the receiving stations. We successfully applied this technique to realistic simulations of ionospheric density variations over 16 degree of latitude and a height range of 50 to 1000 km. A method for approximating the peak height and scale height of the electron density profile will be discussed as well as a reconstruction technique based on the multiplicative algebraic reconstruction technique algorithm and a back projection based initial guess. The quality of reconstructions is considered for two geometries and image resolutions. In particular, the image of a mid-latitude trough with background horizontal density gradient and large-scale irregular structures has been reconstructed from TEC data generated from a model based on an incoherent scatter radar observation. The CT reconstructed image was compared with the original contour map obtained by the incoherent scatter radar. Good agreement has been achieved. The CIT technique has also been applied to a modeled ionosphere to calculate the range rate corrections for a Doppler-tracking radar. Reprint

  17. Didactics and training in cardiovascular computed tomography angiography.

    Science.gov (United States)

    Bhojraj, Sanjay D; Al-Mallah, Mouaz H

    2009-01-01

    As the role of cardiovascular computed tomography angiography (CCTA) is further expanded through research, the use of this technology will expand as a result of demand both from medical professionals and the public. To ensure a standardized quality of interpretation of these scans in the face of an increased demand for physicians qualified to interpret these studies, the Society of Cardiovascular Computed Tomography, along with several other professional societies, has proposed a didactic curriculum for the study of CCTA. This review highlights the currently proposed didactic curriculum for the study of CCTA, examines current trends in training for both medical trainees and physicians in practice, and proposes future directions for the study of CCTA.

  18. Optical coherence tomography angiography versus fluorescein angiography in the diagnosis of ischaemic diabetic maculopathy.

    Science.gov (United States)

    Cennamo, Gilda; Romano, Mario R; Nicoletti, Giuseppe; Velotti, Nunzio; de Crecchio, Giuseppe

    2017-02-01

    To evaluate the efficacy of optical coherence tomography (OCT) angiography versus fluorescein angiography (FA) in terms of retinal vessel imaging in ischaemic diabetic maculopathy defined according to the Early Treatment Diabetic Retinopathy Study (ETDRS) classification. Twenty patients (31 eyes) with ischaemic diabetic maculopathy and 17 control subjects (27 eyes) were enrolled in this prospective study. Patients and control subjects underwent complete ophthalmic examination, including best-corrected visual acuity (BCVA), intraocular pressure, FA, Fourier domain optical coherence tomography (FD-OCT) and OCT angiography. Fluorescein angiograms and OCT angiography images were graded according to the foveal avascular zone (FAZ) of the ETDRS group. Ganglion cell complex (GCC) thickness was evaluated with FD-OCT. Optical coherence tomography (OCT) angiography images closely correlated with FA in terms of FAZ parameters. The correlation was strongest with OCT angiography deep imaging. The average GCC thickness was smaller in patients than in controls. Neither GCC parameters nor FAZ was correlated to BCVA. Given the correlation between FA and OCT angiography in terms of FAZ parameters, the newer method can be considered a valid, reliable and easy-to-perform method with which to evaluate ischaemic diabetic maculopathy without contrast injection, and thus to visualize and quantify non-perfusion areas without risks of anaphylactic reactions. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  19. Optical coherence tomography angiography findings in laser maculopathy.

    Science.gov (United States)

    Tomasso, Livia; Benatti, Lucia; La Spina, Carlo; Lattanzio, Rosangela; Baldin, Giovanni; Carnevali, Adriano; De Vitis, Luigi A; Querques, Lea; Bandello, Francesco; Querques, Giuseppe

    2017-01-19

    Handheld laser pointer thermal injury affects primarily the retinal pigment epithelium (RPE). However, so far no study has reported on the possible effects of laser pointers in the deeper layers, beneath the RPE. Here, we describe the spectral-domain optical coherence tomography angiography findings in the choriocapillaris of a patient with laser maculopathy. A 13-year-old boy presented to our department with decreased vision in the left eye 12 hours after having stared at the beam of a laser pointer. Structural optical coherence tomography (OCT) showed 2 focal hyperreflective columns at the fovea extending from the RPE, involving all outer retinal layers, and terminating at the outer plexiform layer. The patient also underwent OCT angiography (OCT-A), which in the choriocapillary segmentation revealed 2 hypointense lesions in correspondence of the focal hyperreflectivities detected on structural OCT. We hypothesize that the OCT-A findings could represent a rarefaction of the choriocapillaris. However, the choriocapillary OCT-A findings could also represent artifacts due to the overlaying hyperreflective lesions. It is known that the RPE is primarily damaged by the laser injury. Our findings suggest that the thermal injury could involve also the choriocapillaris, and thus not limited to the RPE. Multimodal imaging in laser maculopathy including OCT-A may lead to a better comprehension of the pathogenesis of laser retinal damages.

  20. Differential diagnosis in computerized tomography. 2. rev. and enl. ed.; Differenzialdiagnosen in der Computertomografie

    Energy Technology Data Exchange (ETDEWEB)

    Burgener, Francis A.; Meyers, Steven P. [Rochester Univ., NY (United States). Dept. of Imaging Sciences; Herzog, Christopher [Rotkreuzklinikum Muenchen (Germany); Zaunbauer, Wolfgang [Kantonsspital St. Gallen (Switzerland). Inst. fuer Radiologie

    2013-02-01

    The book on differential diagnosis in computerized tomography is aimed to support radiologists and physicians with experience concerning the interpretation of computerized tomography images by detailed descriptions of CT diagnoses. The book covers the following topics: intracranial indications, head and neck, spinal cord, muscle-skeleton system, thorax, abdomen and pelvis.

  1. Diagnostic performance of computed tomography angiography and contrast-enhanced magnetic resonance angiography in patients with critical limb ischaemia and intermittent claudication: systematic review and meta-analysis

    NARCIS (Netherlands)

    Jens, Sjoerd; Koelemay, Mark J. W.; Reekers, Jim A.; Bipat, Shandra

    2013-01-01

    To evaluate the diagnostic performance of computed tomography angiography (CTA) and contrast-enhanced magnetic resonance angiography (CE-MRA) in detecting haemodynamically significant arterial stenosis or occlusion in patients with critical limb ischaemia (CLI) or intermittent claudication (IC).

  2. Assessment of computerized tomography devices in Minas Gerais state, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Paulo Marcio C., E-mail: pmco@cdtn.br, E-mail: ambienttal@ambienttal.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Horta, Mara Alice Avelar Saraiva [Faculdade Sao Camilo de Minas Gerais - FASC - MG, Graduacao de Tecnologia em Radiologia (Brazil); Santana, Priscila do Carmo [Programa de Pos Graduacao em Ciencias e Tecnicas Nucleares - PCTN, Universidade Federal de Minas Gerais (UFMG) Belo Horizonte, MG (Brazil); Magalhaes, Marcos Juliano [Ambienttal Protecao Radiologica Ltda., Belo Horizonte, MG (Brazil)

    2011-07-01

    Computed Tomography (CT) is the diagnostic imaging method most commonly performed today. It is a device that is undergoing a technological evolution and their quality control is sorely needed. The image quality evaluation process allow a better diagnosis and control of the patient dose received during image acquisition. The CT doses are higher than other X-ray examination techniques, like a conventional X-ray. Performance evaluation of computed tomography in Minas Gerais is not significant. Therefore, this work aims to analyze 20 CT equipment in Minas Gerais, with parameters according to the national regulatory agency (ANVISA - Agencia Nacional de Vigilancia Sanitaria) in twelve quality control tests. Sixty five percent (65%) of CT equipment evaluated showed excellent results and were not disapproved in any of the tests performed and 30% had failed in only one of the twelve tests performed. The worst result was found in the CT scanners in the test that evaluates the low contrast resolution, where 20% of CT showed non-compliance, followed by the test that evaluates the x-rays collimation beam, where 15% had failed. The tests allowed us to observe that the twenty computerized tomography equipment achieved a great pass rate. Considering that the evaluated CTs performed the quality control tests for the first time, it is concluded that the equipment used in clinics and hospitals are of good quality image and low radiation doses. (author)

  3. Analysis of the mental foramen using cone beam computerized tomography

    Directory of Open Access Journals (Sweden)

    Kunihiro Saito

    Full Text Available AbstractIntroductionKnowledge of the anatomical structures located in the region between the mental foramina is of critical importance in pre-operative planning.ObjectiveTo evaluate the position of the mental foramen relative to the apices of the teeth and the distance to the edges of the mandible, using cone beam computerized tomography.Material and methodOne hundred cone beam computerized tomographs of the mandible were evaluated; the tomographs were taken using a single tomographic device. Each image chosen was evaluated repeatedly from both sides of the mandible, the position of the mental foramen, indicating the region in which the foramen was found and the measures of the mental foramen, the lingual cortex and the mandibular base. Initially, the data were analyzed descriptively. A value of pResultForty-two percent of the mental foramina were located in the apex of the second pre-molar. The lingual margin of the mental foramen was located, on average, 3.1mm from the lingual cortex. The lower margin of the mental foramen was located 7.25 mm above the lower edge of the mandible.ConclusionThe mental foramen was located more frequently at a level of the apices of the second pre-molars, with a distance to the lingual cortex, on average, of 3.1mm and to the base of the mandible, on average, of 7.25 mm.

  4. Computerized Tomography with Total Variation and with Shearlets

    CERN Document Server

    Garduño, Edgar

    2016-01-01

    To reduce the x-ray dose in computerized tomography (CT), many constrained optimization approaches have been proposed aiming at minimizing a regularizing function that measures lack of consistency with some prior knowledge about the object that is being imaged, subject to a (predetermined) level of consistency with the detected attenuation of x-rays. Proponents of the shearlet transform in the regularizing function claim that the reconstructions so obtained are better than those produced using TV for texture preservation (but may be worse for noise reduction). In this paper we report results related to this claim. In our reported experiments using simulated CT data collection of the head, reconstructions whose shearlet transform has a small $\\ell_1$-norm are not more efficacious than reconstructions that have a small TV value. Our experiments for making such comparisons use the recently-developed superiorization methodology for both regularizing functions. Superiorization is an automated procedure for turning...

  5. Motion Estimation and Compensation Strategies in Dynamic Computerized Tomography

    Science.gov (United States)

    Hahn, Bernadette N.

    2017-12-01

    A main challenge in computerized tomography consists in imaging moving objects. Temporal changes during the measuring process lead to inconsistent data sets, and applying standard reconstruction techniques causes motion artefacts which can severely impose a reliable diagnostics. Therefore, novel reconstruction techniques are required which compensate for the dynamic behavior. This article builds on recent results from a microlocal analysis of the dynamic setting, which enable us to formulate efficient analytic motion compensation algorithms for contour extraction. Since these methods require information about the dynamic behavior, we further introduce a motion estimation approach which determines parameters of affine and certain non-affine deformations directly from measured motion-corrupted Radon-data. Our methods are illustrated with numerical examples for both types of motion.

  6. Application of computerized tomography to the investigation of ionospheric structures

    Energy Technology Data Exchange (ETDEWEB)

    Raymund, T.D.; Franke, S.J.; Liu, C.H.; Austen, J.R.; Klobuchar, J.A. (Illinois Univ., Urbana (USA) Tennessee Technological Univ., Cookeville (USA) USAF, Geophysics Laboratory, Hanscom AFB, MA (USA))

    1990-10-01

    It is shown that ionospheric total electron content measurements, obtained simultaneously at several locations, can be processed using computerized tomography (CT) algorithms to obtain two-dimensional images of ionospheric electron density. CT, using ionospheric total electron content data, is applied to simulate density variations over 16 deg of latitude and a height range of 50 to 1000 km. A method of approximating the peak height and scale height of the electron density profile is presented, as well as a reconstruction technique using a multiplicative algebraic algorithm and a back projection based initial guess. The quality of the images is examined for two geometries and resolutions. It is suggested that the reconstruction algorithm is sufficiently robust to perform well even in the presence of broad-band noise of reasonable level. 12 refs.

  7. Weight-based contrast administration in the computerized tomography evaluation of acute pulmonary embolism

    Science.gov (United States)

    Laurent, Lisa; Zamfirova, Ina; Sulo, Suela; Baral, Pesach

    2017-01-01

    Abstract Compare individualized contrast protocol, or weight-based protocol, to standard methodology in evaluating acute pulmonary embolism. Retrospective chart review was performed on patients undergoing computed tomography angiography with standard contrast protocol (n = 50) or individualized protocol (n = 50). Computerized tomography images were assessed for vascular enhancement and image quality. Demographics were comparable, however, more patients in the individualized group were admitted to intensive care unit (48% vs 16%, P = 0.004). Vascular enhancement and image quality were also comparable, although individualized protocol had significantly fewer contrast and motion artifact limitations (28% vs 48%, P = 0.039). Fifteen percent decrease in intravenous contrast volume was identified in individualized group with no compromise in image quality. Individualized contrast protocol provided comparable vascular enhancement and image quality to the standard, yet with fewer limitations and lower intravenous contrast volume. Catheter-gauge flow rate restrictions resulting in inconsistent technologist exam execution were identified, supporting the need for further investigation of this regimen. PMID:28151887

  8. Catheter Angiography

    Medline Plus

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

  9. Catheter Angiography

    Medline Plus

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

  10. Statistical analysis of motion contrast in optical coherence tomography angiography

    CERN Document Server

    Cheng, Yuxuan; Pan, Cong; Lu, Tongtong; Hong, Tianyu; Ding, Zhihua; Li, Peng

    2015-01-01

    Optical coherence tomography angiography (Angio-OCT), mainly based on the temporal dynamics of OCT scattering signals, has found a range of potential applications in clinical and scientific researches. In this work, based on the model of random phasor sums, temporal statistics of the complex-valued OCT signals are mathematically described. Statistical distributions of the amplitude differential (AD) and complex differential (CD) Angio-OCT signals are derived. The theories are validated through the flow phantom and live animal experiments. Using the model developed in this work, the origin of the motion contrast in Angio-OCT is mathematically explained, and the implications in the improvement of motion contrast are further discussed, including threshold determination and its residual classification error, averaging method, and scanning protocol. The proposed mathematical model of Angio-OCT signals can aid in the optimal design of the system and associated algorithms.

  11. Optical Coherence Tomography Angiography and En Face Optical Coherence Tomography Features of Paracentral Acute Middle Maculopathy.

    Science.gov (United States)

    Sridhar, Jayanth; Shahlaee, Abtin; Rahimy, Ehsan; Hong, Bryan K; Khan, M Ali; Maguire, Joseph I; Dunn, James P; Mehta, Sonia; Ho, Allen C

    2015-12-01

    To characterize the optical coherence tomography (OCT) angiography, en face OCT, and microperimetry features of paracentral acute middle maculopathy in both the acute phase and after resolution, and to propose a classification of distinct subtypes of this entity. Retrospective observational case series. Clinical histories, high-resolution digital color imaging, spectral-domain OCT images, fluorescein angiography, OCT angiography images, and en face OCT images of 16 patients with paracentral acute middle maculopathy were evaluated. Microperimetry was available in 6 patients. The most common referring diagnoses were isolated branch retinal arterial occlusion (5/16), combined central retinal vein and cilioretinal artery occlusion (4/16), and isolated central retinal vein occlusion (4/16). All patients demonstrated hyperreflective plaque-like lesions at the level of the inner nuclear layer on spectral-domain OCT, with no fluorescein angiographic correlate. OCT angiography demonstrated variable areas of capillary dropout within the superficial and deep retinal capillary plexi in these areas. En face OCT highlighted confluent areas of middle retina hyperreflectivity corresponding to these lesions. Three distinct en face OCT patterns were observed: arteriolar, fern-like, and globular. Microperimetry demonstrated relative scotomas mapping to the area of middle retinal hyperreflectivity seen on en face OCT. Paracentral acute middle maculopathy may be best evaluated with the use of en face OCT imaging, which corresponds to subjective and objective visual field defects. En face OCT appearance may be used to classify paracentral acute maculopathy into distinct subtypes. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Diabetic Macular Ischemia Diagnosis: Comparison between Optical Coherence Tomography Angiography and Fluorescein Angiography

    Directory of Open Access Journals (Sweden)

    Jose Mauricio Botto de Barros Garcia

    2016-01-01

    Full Text Available Purpose. To compare fluorescein angiography (FA and optical coherence tomography angiography (OCTA images of foveal avascular zone (FAZ in patients with diabetic retinopathy (DR with and without diabetic macular ischemia (DMI. Methods. The Wilcoxon signed-rank test was used to compare area measurements and p values of <0.05 were considered statistically significant. FA and OCTA images were independently graded by 2 observers that reached agreement regarding quantitative DMI according established protocols. The ischemic area was divided into “large” macular ischemia (superior to 0.32 mm2 and “small” (inferior to 0.32 mm2 groups. Quantitative analyses of the FAZ were performed using custom software. Results. Thirty-four eyes from 34 diabetic patients were enrolled. Subjects with DMI presented a mean area on FA and OCTA of 0.68 ± 0.53 mm2 and 0.58 ± 0.35 mm2, respectively (p=0.1374. Patients without DMI presented a mean area on FA and OCTA of 0.19 ± 0.67 mm2 and 0.20 ± 0.79 mm2, respectively (p=0.9594. The ICC for the FAZ measurements between the 2 observers on FA and OCTA was 0.96 and 0.92, respectively. Conclusion. OCTA represents a novel technique for the diagnosis of DMI and it may become an alternative to FA for this purpose.

  13. Myocardial bridging: evaluation with multislice computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Barros, M.V.L. de; Rabelo, D.R.; Nunes, M.C.P.; Siqueira, M.H.A. [Mater Dei Hospital, Belo Horizonte, MG (Brazil)

    2012-04-15

    Myocardial bridging (MB) is defined as a segment of a major epicardial coronary artery that proceeds intramurally through the myocardium beneath the muscle bridge. Although MB is clinically silent in most cases, it has been associated with myocardial ischemia, myocardial infarction, arrhythmia, and sudden death. Conventional coronary angiography (CCA) is the gold standard for detection, but it is invasive and may not be sensitive enough to detect a thin bridge. Recently, multislice computed tomography coronary angiography (MCTCA) have made possible the clear detection of the entire running courses of coronary arteries and the MB itself. Objective: To evaluate the prevalence MB in patients suspect to coronary artery disease submitted to MCTCA and assessing the predictive value of this method in the midterm. Methods: 498 consecutive patients were examined by MCTCA for the diagnosis of coronary artery disease and followed for a mean follow-up of 17 months for the occurrence of cardiovascular events (death, hospitalization and / or revascularization myocardial). Results: The mean age of patients was 58.4 ± 12.5 years old, 74.3% male. Among the patients, 6,02% (30 patients) showed MB. The major indications were angina pectoris in 45,8% and positive stress testing in 33,3%. 62,5% showed absent atherosclerotic disease and only 1 patient showed moderade descending anterior stenosis. During the follow-up none patient showed hard events. Conclusion: Patients with MB could present with angina pectoris and positive stress testing and showed midterm excellent prognosis. MCTCA is an alternative noninvasive imaging tool that allows for easy and accurate evaluation of MB.

  14. Sublingual Nitroglycerin Administration in Coronary Computed Tomography Angiography : a Systematic Review

    NARCIS (Netherlands)

    Takx, Richard A. P.; Suchá, D.; Park, Jakob; Leiner, Tim; Hoffmann, Udo

    2015-01-01

    To systematically investigate the literature for the influence of sublingual nitroglycerin administration on coronary diameter, the number of evaluable segments, image quality, heart rate and blood pressure, and diagnostic accuracy of coronary computed tomography (CT) angiography. A systematic

  15. Computerized tomography of Castleman's disease simulating a false renal artery aneurysm: a case report.

    Science.gov (United States)

    Friedman, L; Dubowitz, B; Papert, B; Porteous, P

    1987-07-01

    We report a case of retroperitoneal Castleman's disease of the hyaline vascular type simulating a false renal artery aneurysm. Excretory urography with computerized tomography and angiographic findings are presented. All 3 investigations demonstrated a homogeneously enhancing hypervascular retroperitoneal mass.

  16. An alternative approach to computerized tomography (CT) in forensic pathology.

    Science.gov (United States)

    Thomsen, Asser H; Jurik, Anne Grethe; Uhrenholt, Lars; Vesterby, Annie

    2009-01-10

    Computerized Tomography (CT) is used by some forensic pathology departments as a supplement to the forensic autopsy. Departments with a limited number of autopsies may find it relatively expensive to acquire and operate a CT-scanner. Furthermore, it requires a great deal of training and experience to interpret the radiological data. We are currently evaluating CT in order to decide whether the benefits match the efforts. In selected death-investigations the Department of Radiology at Aarhus University Hospital performs CT of the body on behalf of the Institute of Forensic Medicine at Aarhus University and a skilled radiologist interprets the data. We present our radiological findings in the 20 cases where we have used CT and compare them to the autopsy findings. The cases include fatalities from beatings, stabbings, gunshots, fires and traffic accidents. CT is an excellent tool for documenting and illustrating certain lesions, such as gunshot wounds and bone fractures, where we can obtain information that possibly would have been missed at the autopsy. We believe, however, that further research is required before we can recommend CT as a part of a standard forensic autopsy. The cooperation between forensic and radiological departments is a good approach for smaller forensic departments that insures a skilled interpretation without having to divert a lot of resources to equipment and training.

  17. Percutaneous nephrolithotomy in pediatric patients: is computerized tomography a must?

    Science.gov (United States)

    Gedik, Abdullah; Tutus, Ali; Kayan, Devrim; Yılmaz, Yakup; Bircan, Kamuran

    2011-02-01

    The aim of this study was to retrospectively evaluate the results of pediatric percutaneous nephrolithotomy (PNL) cases, and discuss the results and necessity of non-contrast computerized tomography (CT) in these cases. In all, 48 pediatric patients who underwent PNL were retrospectively evaluated. Before PNL, either intravenous urography or CT was performed. In all patients, we evaluated the PNL time, scopy time with stone burden, and complications. During the PNL procedure, we switched to open surgery in two cases: in one because of renal pelvis perforation and in the other because of transcolonic access. In one patient who was scheduled to undergo PNL, we performed open surgery, primarily because we detected a retrorenal colon with CT. The stone burden in 45 patients who underwent PNL was 445 ± 225 mm(2), the PNL time was 51 ± 23 min, and the scopy time was 6.1 ± 2.7 min. We removed nephrostomy tubes 1-4 days after the procedure. In two patients, 24 h after removal of nephrostomy tubes, we inserted double J stents because of prolonged urine extravasation from the tract. In all, 34 of the 45 patients were stone-free, 5 patients had clinically insignificant stone fragments, and 6 patients had residual stones. PNL is a safe and effective method in the treatment of pediatric patients with kidney stones. Clinical experience is the most important factor in obtaining stone-free results. CT should be performed in all pediatric patients in order to prevent colon perforation.

  18. Trauma surgeon utilization of computerized tomography scanning: Room for improvement?

    Science.gov (United States)

    Ong, Adrian W; Moyer, Jeffery; Wordofa, Fikir D; Sigal, Adam; Sandel, Kristen; Fernandez, Forrest B

    2017-03-01

    We aimed to evaluate computerized tomography (CT) utilization and yield rates for trauma team activations (TTA). A retrospective review of all TTAs was conducted over nine months. TTAs consisted of two levels--trauma alert (TAL) and trauma response (TR). Yields of CT for significant findings (SF) for four CT types (brain, cervical, chest, abdomen/pelvis) were recorded. 647 patients were included. There was no difference in the utilization rates of CTs except for brain CTs (TAL, 98% vs TR, 94%, p = 0.008). There was no difference in the yield rates except for cervical spine CTs (TAL, 8% vs TR, 4%, p = 0.03). Over 80% received a pan scan regardless of TTA level; 63% who had any CT had no SF. The median ratio of scans with SF to the total number of scans per patient was 0. Regardless of activation level, CT seems to be over utilized. More selective use of CT should be evaluated. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Diagnostic Value of Dual-Source Computerized Tomography Combined with Perfusion Imaging for Peripheral Pulmonary Embolism

    Science.gov (United States)

    Mao, Xijin; Wang, Shanshan; Jiang, Xingyue; Zhang, Lin; Xu, Wenjian

    2016-01-01

    Background Pulmonary embolism has become the third most common cardiovascular disease, which can seriously harm human health. Objectives To investigate the diagnostic value of dual-source computerized tomography (CT) and perfusion imaging for peripheral pulmonary embolism. Patients and Methods Thirty-two patients with suspected pulmonary embolism underwent dual-source CT exams. To compare the ability of pulmonary embolism detection software (PED) with CT pulmonary angiography (CTPA) in determining the presence, numbers, and locations of pulmonary emboli, the subsequent images were reviewed by two radiologists using both imaging modalities. Also, the diagnostic consistency between PED and CTPA images and dual-energy pulmonary perfusion imaging (DEPI) for segmental pulmonary embolism was compared. Results CTPA images revealed 50 (7.81%) segmental and 56 (4.38%) sub-segmental pulmonary embolisms, while the PED images showed 68 (10.63%) segmental and 94 (7.34%) sub-segmental pulmonary embolisms. Thus, the detection rate on PED images for peripheral pulmonary embolism was significantly higher than that of the CTPA images (P pulmonary embolism between PED and CTPA and DEPI (kappa = 0.85). The sensitivity and specificity of DEPI images for the diagnosis of pulmonary embolism were 91.7% and 97.5%, respectively. Conclusion PED software of dual-source CT combined with perfusion imaging can significantly improve the detection rate of peripheral pulmonary embolism. PMID:27703656

  20. Diagnostic performance of computed tomography angiography in peripheral arterial disease: a systematic review and meta-analysis

    NARCIS (Netherlands)

    Met, Rosemarie; Bipat, Shandra; Legemate, Dink A.; Reekers, Jim A.; Koelemay, Mark J. W.

    2009-01-01

    CONTEXT: Computed tomography angiography (CTA) is an increasingly attractive imaging modality for assessing lower extremity peripheral arterial disease (PAD). OBJECTIVE: To determine the accuracy of CTA compared with intra-arterial digital subtraction angiography (DSA) in differentiating extent of

  1. Computerized tomography with 3-dimensional reconstruction for the evaluation of renal size and arterial anatomy in the living kidney donor.

    Science.gov (United States)

    Janoff, Daniel M; Davol, Patrick; Hazzard, James; Lemmers, Michael J; Paduch, Darius A; Barry, John M

    2004-01-01

    Computerized tomography (CT) with 3-dimensional (3-D) reconstruction has gained acceptance as an imaging study to evaluate living renal donors. We report our experience with this technique in 199 consecutive patients to validate its predictions of arterial anatomy and kidney volumes. Between January 1997 and March 2002, 199 living donor nephrectomies were performed at our institution using an open technique. During the operation arterial anatomy was recorded as well as kidney weight in 98 patients and displacement volume in 27. Each donor had been evaluated preoperatively by CT angiography with 3-D reconstruction. Arterial anatomy described by a staff radiologist was compared with intraoperative findings. CT estimated volumes were reported. Linear correlation graphs were generated to assess the reliability of CT volume predictions. The accuracy of CT angiography for predicting arterial anatomy was 90.5%. However, as the number of renal arteries increased, predictive accuracy decreased. The ability of CT to predict multiple arteries remained high with a positive predictive value of 95.2%. Calculated CT volume and kidney weight significantly correlated (0.654). However, the coefficient of variation index (how much average CT volume differed from measured intraoperative volume) was 17.8%. CT angiography with 3-D reconstruction accurately predicts arterial vasculature in more than 90% of patients and it can be used to compare renal volumes. However, accuracy decreases with multiple renal arteries and volume comparisons may be inaccurate when the difference in kidney volumes is within 17.8%.

  2. Evaluation of preoperative computed tomography angiography in association with conventional angiography versus computed tomography angiography only, in the endovascular treatment of aortic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Patrick Bastos; Novero, Eduardo Rafael; Rossi, Fabio Henrique; Moreira, Samuel Martins; Linhares, Frederico Augusto; Almeida, Bruno Lorencao de; Barbato, Heraldo Antonio; Izukawa, Nilo Mitsuru; Kambara, Antonio Massamitsu, E-mail: patrickvascular@gmail.com [Instituto Dante Pazzanese de Cardiologia, Sao Paulo, SP (Brazil)

    2013-09-15

    Objective: to evaluate the association of conventional angiography (AG) with computed tomography angiography (CTA) as compared with CTA only, preoperatively, in the treatment of aortic diseases. Materials and methods: retrospective study involving patients submitted to endovascular treatment of aortic diseases, in the period from January 2009 to July 2010, with use of preoperative CTA + conventional AG or CTA only. The patients were divided into two groups, namely: G1 - thoracic aortic diseases; and G2 - abdominal aortic diseases. G1 was subdivided into 1A (preoperative AG + CTA) and 1B (preoperative CTA). G2 was subdivided into 2C (CTA + AG) and 2D (CTA only). Results: the authors evaluated 156 patients. In subgroups 1A and 1B, the rate of technical success was, respectively, 100% and 94.7% (p = 1.0); and the rate of therapeutic success was, respectively, 81% and 58% (p = 0.13). A higher number of complications were observed in subgroup 1B (p = 0.057). The accuracy in the calculation of the prosthesis was higher in subgroup 1A (p = 0.065). In their turn, the rate of technical success in subgroups 2C and 2D was, respectively, 92.3% and 98.6% (p = 0.17). The rate of therapeutic success was 73% and 98.6% (p = 0.79). Conclusion: preoperative conventional AG should be reserved for cases where CTA cannot provide all the information in the planning of a therapeutic intervention. (author)

  3. First results of computerised tomographic angiography using electron beam tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, K.J.; Weisser, G.; Neff, K.W.; Mai, S.K.; Denk, S.; Georgi, M. [Inst. fuer Klinische Radiologie, Universitaetsklinikum Mannheim, Heidelberg (Germany)

    1999-05-01

    The aim of this study was to evaluate the suitability of electron beam tomography (EBT) with fast continuous volume scanning for CT angiography (CTA) in chest and abdomen. An Evolution XP EBT scanner with a new software version (12.34) was used. One hundred forty images per study can be acquired in 17 s using 3-mm collimation and overlapping image reconstruction. Study protocols for five different clinical applications of EBT CTA were established and evaluated. The EBT CTA technique was performed in 155 patients. High- and homogeneous density values were achieved along the whole course of the vessels; the mean density in the aorta was > 240 HU. Coeliac axis, superior and inferior mesenteric artery, renal and lumbar arteries were visualised in all cases. Maximum intensity projection and shaded surface display reconstruction demonstrated the relation between aneurysm and aortic branches very well due to an excellent resolution along the z-axis. In large scan volumes overlapping image reconstruction demonstrated better resolution along the z-axis than is available with helical CT. The EBT CTA technique proved to be very well suited excellent suitability for evaluation of pulmonary vessels. Compared with helical CT, EBT CTA offers a shorter scan time, which allows higher contrast enhancement in pulmonary vessels. The identification of intraluminal emboli and mural thrombi has improved. The EBT CTA technique is a very reliable tool for evaluation of aortic disease and pulmonary vessels. (orig.) With 3 figs., 9 refs.

  4. OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES OF TORPEDO MACULOPATHY.

    Science.gov (United States)

    Giannakaki-Zimmermann, Helena; Munk, Marion R; Dysli, Chantal; Ebneter, Andreas; Wolf, Sebastian; Zinkernagel, Martin S

    2017-04-03

    To investigate the retinal and choroidal vasculature in patients with torpedo maculopathy with optical coherence tomography-angiography (OCT-A). Retrospective case series of four patients who were examined at the department of Ophthalmology at the University Hospital Bern. Main Outcome was the lesion size over time in OCT-A and fundus autofluorescence. Three patients had Type I and 1 patient had Type II torpedo maculopathy. Torpedo maculopathy lesion size remained stable in all patients over a mean period of observation of three years in OCT-A and fundus autofluorescence. The choriocapillaris network was attenuated focally within the lesion in OCT-A in all four cases. The lesion size in fundus autofluorescence was 2.77 mm and therefore comparable with the lesion size in OCT-A of 2.75 mm. OCT-A signal of the choriocapillaris was reduced within the cleft in both types of torpedo maculopathy. Whether the changes represent the primary site of malformation or whether these findings are the consequence of a defect in the retinal pigment epithelium remains speculative.

  5. Assessment of the Circle of Willis with Cranial Tomography Angiography.

    Science.gov (United States)

    Karatas, Ayse; Coban, Gokmen; Cinar, Celal; Oran, Ismail; Uz, Aysun

    2015-09-06

    The circle of Willis is a major collateral pathway important in ischemic conditions. The aim of our study was to assess the structural characteristics of the circle of Willis within the Turkish adult population, along with variations and arteries involved in the measurement of diameters and lengths on cranial computed tomography angiography (CTA). One hundred adult patients who underwent CTA images were evaluated retrospectively. Results of the study revealed 82% adult, 17% fetal, and 1% transitional configurations. A complete polygonal structure was observed in 28% of cases. Variations of the circle of Willis were more common in the posterior portion. Hypoplasia was found to be the most common variation and was observed as a maximum in the posterior communicating artery (AComP). The patency and size of arteries in the circle of Willis are important in occlusive cerebrovascular diseases and cerebrovascular surgery. Although CTA is an easily accessible non-invasive clinical method for demonstrating the vascular structure, CTA should be evaluated taking into account image resolution quality and difficulties in the identification of small vessels.

  6. Accuracy of coronary computed tomography angiography for bioresorbable scaffold luminal investigation: a comparison with optical coherence tomography

    NARCIS (Netherlands)

    Collet, Carlos; Sotomi, Yohei; Cavalcante, Rafael; Asano, Taku; Miyazaki, Yosuke; Tenekecioglu, Erhan; Kistlaar, Pieter; Zeng, Yaping; Suwanasson, Pannipa; de Winter, Robbert J.; Nieman, Koen; Serruys, Patrick W.; Onuma, Yoshinobu

    2017-01-01

    To establish the accuracy of coronary computed tomography angiography (CTA) for in-scaffold quantitative evaluation with optical coherence tomography (OCT) as a reference. The translucent backbone of the bioresorbable scaffold allow us to evaluate non-invasively the coronary lumen with coronary CTA.

  7. Computerized tomography with total variation and with shearlets

    Science.gov (United States)

    Garduño, Edgar; Herman, Gabor T.

    2017-04-01

    To reduce the x-ray dose in computerized tomography (CT), many constrained optimization approaches have been proposed aiming at minimizing a regularizing function that measures a lack of consistency with some prior knowledge about the object that is being imaged, subject to a (predetermined) level of consistency with the detected attenuation of x-rays. One commonly investigated regularizing function is total variation (TV), while other publications advocate the use of some type of multiscale geometric transform in the definition of the regularizing function, a particular recent choice for this is the shearlet transform. Proponents of the shearlet transform in the regularizing function claim that the reconstructions so obtained are better than those produced using TV for texture preservation (but may be worse for noise reduction). In this paper we report results related to this claim. In our reported experiments using simulated CT data collection of the head, reconstructions whose shearlet transform has a small ℓ 1-norm are not more efficacious than reconstructions that have a small TV value. Our experiments for making such comparisons use the recently-developed superiorization methodology for both regularizing functions. Superiorization is an automated procedure for turning an iterative algorithm for producing images that satisfy a primary criterion (such as consistency with the observed measurements) into its superiorized version that will produce results that, according to the primary criterion are as good as those produced by the original algorithm, but in addition are superior to them according to a secondary (regularizing) criterion. The method presented for superiorization involving the ℓ 1-norm of the shearlet transform is novel and is quite general: It can be used for any regularizing function that is defined as the ℓ 1-norm of a transform specified by the application of a matrix. Because in the previous literature the split Bregman algorithm is used

  8. Multidetector computed tomography pulmonary angiography in childhood acute pulmonary embolism

    Science.gov (United States)

    Tang, Chun Xiang; Schoepf, U. Joseph; Chowdhury, Shahryar M.; Fox, Mary A.; Lu, Guang Ming

    2015-01-01

    Pulmonary embolism is a life-threatening condition affecting people of all ages. Multidetector row CT pulmonary angiography has improved the imaging of pulmonary embolism in both adults and children and is now regarded as the routine modality for detection of pulmonary embolism. Advanced CT pulmonary angiography techniques developed in recent years, such as dual-energy CT, have been applied as a one-stop modality for pulmonary embolism diagnosis in children, as they can simultaneously provide anatomical and functional information. We discuss CT pulmonary angiography techniques, common and uncommon findings of pulmonary embolism in both conventional and dual-energy CT pulmonary angiography, and radiation dose considerations. PMID:25846076

  9. Multidetector computed tomography pulmonary angiography in childhood acute pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chun Xiang; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Department of Pediatrics, Charleston, SC (United States); Chowdhury, Shahryar M. [Medical University of South Carolina, Department of Pediatrics, Charleston, SC (United States); Fox, Mary A. [Medical University of South Carolina, Department of Radiology and Radiological Science, Charleston, SC (United States)

    2015-09-15

    Pulmonary embolism is a life-threatening condition affecting people of all ages. Multidetector row CT pulmonary angiography has improved the imaging of pulmonary embolism in both adults and children and is now regarded as the routine modality for detection of pulmonary embolism. Advanced CT pulmonary angiography techniques developed in recent years, such as dual-energy CT, have been applied as a one-stop modality for pulmonary embolism diagnosis in children, as they can simultaneously provide anatomical and functional information. We discuss CT pulmonary angiography techniques, common and uncommon findings of pulmonary embolism in both conventional and dual-energy CT pulmonary angiography, and radiation dose considerations. (orig.)

  10. Optical Coherence Tomography and Optical Coherence Tomography Angiography in Monitoring Coats’ Disease

    Directory of Open Access Journals (Sweden)

    Wojciech Hautz

    2017-01-01

    Full Text Available Purpose. The aim of this study was to evaluate the usefulness of optical coherence tomography (OCT and optical coherence tomography angiography (OCTA in monitoring pediatric patients with Coats’ disease. Material and Methods. This retrospective study included 9 Caucasian patients receiving treatment for Coats’ disease at the Children’s Memorial Health Institute Ophthalmology Department between December 2014 and May 2016. The course of the disease was monitored with OCTA in combination with OCT and fluorescein angiography (FA. Results. OCT B-scans obtained in all patients correlated with FA findings. Reliable OCTA images were obtained in 8 patients. In one patient, numerous artifacts due to poor visual acuity and retinal detachment confounded the interpretation of findings. Conclusions. OCTA and OCT, in combination with FA, are useful in Coats’ disease diagnostics and treatment monitoring. As noninvasive methods, OCT and OCTA may be performed more often than FA, which enable precise monitoring of the disease and making decisions as to its further treatment.

  11. Optical coherence tomography angiography-based capillary velocimetry

    Science.gov (United States)

    Wang, Ruikang K.; Zhang, Qinqin; Li, Yuandong; Song, Shaozhen

    2017-06-01

    Challenge persists in the field of optical coherence tomography (OCT) when it is required to quantify capillary blood flow within tissue beds in vivo. We propose a useful approach to statistically estimate the mean capillary flow velocity using a model-based statistical method of eigendecomposition (ED) analysis of the complex OCT signals obtained with the OCT angiography (OCTA) scanning protocol. ED-based analysis is achieved by the covariance matrix of the ensemble complex OCT signals, upon which the eigenvalues and eigenvectors that represent the subsets of the signal makeup are calculated. From this analysis, the signals due to moving particles can be isolated by employing an adaptive regression filter to remove the eigencomponents that represent static tissue signals. The mean frequency (MF) of moving particles can be estimated by the first lag-one autocorrelation of the corresponding eigenvectors. Three important parameters are introduced, including the blood flow signal power representing the presence of blood flow (i.e., OCTA signals), the MF indicating the mean velocity of blood flow, and the frequency bandwidth describing the temporal flow heterogeneity within a scanned tissue volume. The proposed approach is tested using scattering phantoms, in which microfluidic channels are used to simulate the functional capillary vessels that are perfused with the scattering intralipid solution. The results indicate a linear relationship between the MF and mean flow velocity. In vivo animal experiments are also conducted by imaging mouse brain with distal middle cerebral artery ligation to test the capability of the method to image the changes in capillary flows in response to an ischemic insult, demonstrating the practical usefulness of the proposed method for providing important quantifiable information about capillary tissue beds in the investigations of neurological conditions in vivo.

  12. Coronary Computed Tomography Angiography in the Assessment of Acute Chest Pain in the Emergency Room

    Energy Technology Data Exchange (ETDEWEB)

    Prazeres, Carlos Eduardo Elias dos; Cury, Roberto Caldeira; Carneiro, Adriano Camargo de Castro [Hospital do Coração - HCor, Associação do Sanatório Sírio, São Paulo, SP (Brazil); Rochitte, Carlos Eduardo, E-mail: rochitte@cardiol.br [Hospital do Coração - HCor, Associação do Sanatório Sírio, São Paulo, SP (Brazil); Instituto do Coração - InCor - HCFMUSP, São Paulo, SP (Brazil)

    2013-12-15

    The coronary computed tomography angiography has recently emerged as an accurate diagnostic tool in the evaluation of coronary artery disease, providing diagnostic and prognostic data that correlate directly with the data provided by invasive coronary angiography. The association of recent technological developments has allowed improved temporal resolution and better spatial coverage of the cardiac volume with significant reduction in radiation dose, and with the crucial need for more effective protocols of risk stratification of patients with chest pain in the emergency room, recent evaluation of the computed tomography coronary angiography has been performed in the setting of acute chest pain, as about two thirds of invasive coronary angiographies show no significantly obstructive coronary artery disease. In daily practice, without the use of more efficient technologies, such as coronary angiography by computed tomography, safe and efficient stratification of patients with acute chest pain remains a challenge to the medical team in the emergency room. Recently, several studies, including three randomized trials, showed favorable results with the use of this technology in the emergency department for patients with low to intermediate likelihood of coronary artery disease. In this review, we show data resulting from coronary angiography by computed tomography in risk stratification of patients with chest pain in the emergency room, its diagnostic value, prognosis and cost-effectiveness and a critical analysis of recently published multicenter studies.

  13. Coronary computed tomography angiography in the assessment of acute chest pain in the emergency room.

    Science.gov (United States)

    Prazeres, Carlos Eduardo Elias dos; Cury, Roberto Caldeira; Carneiro, Adriano Camargo de Castro; Rochitte, Carlos Eduardo

    2013-12-01

    The coronary computed tomography angiography has recently emerged as an accurate diagnostic tool in the evaluation of coronary artery disease, providing diagnostic and prognostic data that correlate directly with the data provided by invasive coronary angiography. The association of recent technological developments has allowed improved temporal resolution and better spatial coverage of the cardiac volume with significant reduction in radiation dose, and with the crucial need for more effective protocols of risk stratification of patients with chest pain in the emergency room, recent evaluation of the computed tomography coronary angiography has been performed in the setting of acute chest pain, as about two thirds of invasive coronary angiographies show no significantly obstructive coronary artery disease. In daily practice, without the use of more efficient technologies, such as coronary angiography by computed tomography, safe and efficient stratification of patients with acute chest pain remains a challenge to the medical team in the emergency room. Recently, several studies, including three randomized trials, showed favorable results with the use of this technology in the emergency department for patients with low to intermediate likelihood of coronary artery disease. In this review, we show data resulting from coronary angiography by computed tomography in risk stratification of patients with chest pain in the emergency room, its diagnostic value, prognosis and cost-effectiveness and a critical analysis of recently published multicenter studies.

  14. Computerized tomography-based anatomic description of the porcine liver.

    Science.gov (United States)

    Bekheit, Mohamed; Bucur, Petru O; Wartenberg, Mylene; Vibert, Eric

    2017-04-01

    The knowledge of the anatomic features is imperative for successful modeling of the different surgical situations. This study aims to describe the anatomic features of the porcine using computerized tomography (CT) scan. Thirty large, white, female pigs were included in this study. The CT image acquisition was performed in four-phase contrast study. Subsequently, analysis of the images was performed using syngo.via software (Siemens) to subtract mainly the hepatic artery and its branches. Analysis of the portal and hepatic veins division pattern was performed using the Myrian XP-Liver 1.14.1 software (Intrasense). The mean total liver volume was 915 ± 159 mL. The largest sector in the liver was the right medial one representing around 28 ± 5.7% of the total liver volume. Next in order is the right lateral sector constituting around 24 ± 5%. Its volume is very close to the volume of the left medial sector, which represents around 22 ± 4.7% of the total liver volume. The caudate lobe represents around 8 ± 2% of the total liver volume.The portal vein did not show distinct right and left divisions rather than consecutive branches that come off the main trunk. The hepatic artery frequently trifurcates into left trunk that gives off the right gastric artery and the artery to the left lateral sector, the middle hepatic artery that supplies both the right and the left medial sectors and the right hepatic artery trunk that divides to give anterior branch to the right lateral lobe, branch to the right medial lobe, and at least a branch to the caudate lobe. Frequently, there is a posterior branch that crosses behind the portal vein to the right lateral lobe. The suprahepatic veins join the inferior vena cava in three distinct openings. There are communications between the suprahepatic veins that drain the adjacent sectors. The vein from the right lateral and the right medial sectors drains into a common trunk. The vein from the left lateral and from the left

  15. Intravenous Flat-Detector Computed Tomography Angiography for Symptomatic Cerebral Vasospasm following Aneurysmal Subarachnoid Hemorrhage

    OpenAIRE

    Jin Pyeong Jeon; Seung Hun Sheen; Yong-Jun Cho

    2014-01-01

    The study evaluated the diagnostic accuracy of intravenous flat-detector computed tomography (IV FDCT) angiography in assessing hemodynamically significant cerebral vasospasm in patients with subarachnoid hemorrhage (SAH) with digital subtraction angiography (DSA) as the reference. DSA and IV FDCT were conducted concurrently in patients suspected of having symptomatic cerebral vasospasm postoperatively. The presence and severity of vasospasm were estimated according to location (proximal vers...

  16. Simultaneous bilateral contrast injection in computed tomography pulmonary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Bulla, Stefan; Pache, Gregor; Langer, Mathias; Blanke, Philipp (Department of Diagnostic Radiology, University Hospital Freiburg (Germany)), Email: stefan.bulla@uniklinik-freiburg.de; Bley, Thorsten (Department of Diagnostic Radiology, University Hospital Hamburg (Germany))

    2012-02-15

    Background. Computed tomography pulmonary angiography (CTPA) has evolved as the gold standard for diagnosing pulmonary embolism. However, subsegmental arteries are often not assessed to do insufficient attenuation. Purpose. To evaluate the influence of simultaneous bilateral versus unilateral injection of a fixed amount of contrast media on pulmonary artery opacification and image quality in CTPA. Material and Methods. In this institutional review board-approved prospective study, 180 patients (91 women, mean age 61.9 +- 16.5 years) referred for CTPA (100 kV) due to suspected pulmonary embolism were randomized in groups of 45 patients each, with either unilateral (A:4 mL/s; B:6 mL/s) or bilateral (C: 6 mL/s; D: 8 mL/s) (Y-shaped line) injection of 50 mL contrast media. Attenuation was assessed including the subsegmental arteries (4th order). Image quality was evaluated by two readers in consensus using a three-point grading scale (3 = excellent image quality, no artifacts, 1 = non-diagnostic). Results. Mean pulmonary artery attenuation was significantly higher with bilateral injection (1st to 3rd order: A: 303.6 +- 8.8HU; B: 371.1 +- 11.0HU vs. C: 443.2 +- 24.1HU; D: 562.3 +- 15.3HU, P < 0.001). Evaluation of subsegmental arteries was feasible for all patients in groups B-D, but only in 36/45 (80%) patients in group A. Subsegmental attenuation was significantly higher with bilateral injection (A: 284.7 +- 12.1HU; B: 367.4 +- 12.1HU vs. C: 494.2 +- 21.5HU; D: 562.3 +- 26.7HU, P < 0.001). Image quality was diagnostic for all patients but best for group C (A: 2.15 +- 0.4; B: 2.14 +- 0.5; C: 2.92 +- 0.3, and D: 2.51 +- 0.5). Conclusion. Using the same amount of contrast media, bilateral injection yields higher pulmonary artery attenuation and better image quality than unilateral injection. This technique may improve subsegmental pulmonary artery assessment

  17. Status of routine post-mortem computerized tomography in Odense, Denmark

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2008-01-01

      In February 2006 a dual slice CT scanner was installed at the Institute of Forensic Medicine in Odense, Denmark. Since that time a CT-scanning has been performed on all bodies prior to autopsy. This article provides an overview of the experience gained.  We found that computerized tomography...... rarely is a substitute for autopsy, but may contribute with important new information in many cases such as identifications (including mass-disasters), battered child, gunshot wounds, traffic accidents and air embolism. Computerized tomography provides documentation in digital form - easily stored...

  18. The Role of Coronary Computed Tomography Angiography and Cardiac Magnetic Resonance in STEMI Patients with Normal Coronary Angiography

    Directory of Open Access Journals (Sweden)

    Beganu Elena

    2017-09-01

    Full Text Available Usually, the diagnosis of myocardial infarction based on patient symptoms, electrocardiogram (ECG changes, and cardiac enzymes, is not a challenge for cardiologists. The correlation between coronary anatomy and the ECG territories that present ischemic changes can help the clinician to estimate which coronary artery presents lesions upon performing a coronary angiogram. In certain situations, the diagnosis of myocardial infarction can be difficult due to the lack of correlations between the clinical and paraclinical examinations and the coronary angiogram. In some cases, patients with chest pain and ST-segment elevation on the ECG tracing present with a normal coronary angiography. In other cases, patients without important changes on the ECG can present critical lesions or even occlusions upon angiographic examination. The aim of this article is to highlight the role of noninvasive coronary magnetic resonance and multi-slice computed tomography in patients with ST-segment elevation myocardial infarction and normal coronary angiography.

  19. Positron emission tomography / computerized tomography evaluation of primary Hodgkin's disease of liver.

    Science.gov (United States)

    Gota, V S; Purandare, N C; Gujral, S; Shah, S; Nair, R; Rangarajan, V

    2009-01-01

    Occurrence of primary Hodgkin's lymphoma (PHL) of the liver is extremely rare. We report on a case of a 60-year-old male who presented with liver mass and B-symptomatology. Hepatoma or hepatic metastasis from a gastrointestinal primary was initially suspected. Tumor markers like AFP, CEA, Total PSA, and CA-19.9 were within normal limits. Positron Emission Tomography / Computerized Tomography (PET/CT) revealed a large hepatic lesion and a nodal mass in the porta hepatis. A liver biopsy was consistent with Hodgkin's lymphoma. There was complete regression of the hepatic lesion and evidence of shrinkage of the nodal mass following four cycles of chemotherapy. 18F Fluro -de-oxy Glucose (FDG) PET / CT in this case helped in establishing a primary hepatic lymphoma by demonstrating the absence of pathologically hypermetabolic foci in any other nodes or organs. PET / CT scan is a useful adjunct to conventional imaging and histopathology, not only to establish the initial diagnosis, but also to monitor treatment response in PHL.

  20. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed ...

  1. Atherosclerotic carotid plaque assessment with multidetector computed tomography angiography

    NARCIS (Netherlands)

    T.T. de Weert (Thomas)

    2009-01-01

    textabstractThis thesis evaluates the role of MDCT angiography in 1) the depiction of atherosclerotic disease and subsequent luminal stenosis in the arteries that supplies the brain with blood, and 2) the assessment of atherosclerotic plaque features that have been related to plaque vulnerability.

  2. Can duplex Doppler ultrasound replace computerized tomography in staging patients with renal cell carcinoma?

    NARCIS (Netherlands)

    Bos, SD; Mensink, HJA

    The purpose of this study was to evaluate the accuracy and reliability of duplex Doppler ultrasound (US) and computerized tomography (CT) in staging patients with renal cell carcinoma (RCC). Sixty-six patients were evaluated pre-operatively with duplex Doppler ultrasound and CT. The results were

  3. Computerized tomography (the EMI Scanner): a comparison with pneumoencephalography and ventriculography.

    Science.gov (United States)

    Gawler, J; Du Boulay, G H; Bull, J W; Marshall, J

    1976-01-01

    Computerized tomography, using the EMI Scanner, allows the diagnosis of cerebral atrophy or hydrocephalus to be made with the same degree of accuracy as conventional neuroradiological methods. Ventricular measurements made on EMI scans have been compared with those from pneumoencephalograms and ventriculograms. A range of normal ventricular measurements for the EMI scan is suggested. Images PMID:1084413

  4. Optical coherence tomography angiography artifactual choroidal neovascularization in optic disc pit maculopathy

    Directory of Open Access Journals (Sweden)

    Marina Roizenblatt

    Full Text Available ABSTRACT This case report describes a 19-year-old Caucasian man presented with decreased visual acuity in the right eye for 3 months. Dilated funds exam revealed optic disk pit associated with serous macular detachment. Optical coherence tomography identified communication between the optic disk pit and the macular serous detachment, and optical coherence tomography angiography displayed a subfoveal area suggestive of subfoveal choroidal neovascularization. However, there was no evidence of leakage in the fluorescein angiogram and no evidence of choroidal neovascularization in optical coherence tomography in the area corresponding to the suspicious subfoveal choroidal neovascularization. The patient underwent 23-gauge pars plana vitrectomy in the right eye. Six weeks after surgery, multimodal imaging was repeated and there was near-complete resorption of the subretinal fluid. Optical coherence tomography angiography signal superimposed on optical coherence tomography B-scan also demonstrated normal choriocapillaris signal throughout the macula. In conclusion, optical coherence tomography angiography may produce artifacts in optic disk pit maculopathy that simulate choroidal neovascularization.

  5. Cardiac computed tomography angiography results in diagnostic and therapeutic change in prosthetic heart valve endocarditis

    NARCIS (Netherlands)

    Habets, Jesse; Tanis, Wilco; van Herwerden, Lex A.; van den Brink, Renee B. A.; Mali, Willem P. Th M.; de Mol, Bas A. J. M.; Chamuleau, Steven A. J.; Budde, Ricardo P. J.

    2014-01-01

    Echocardiography may miss prosthetic heart valve (PHV) endocarditis which advocates for novel imaging techniques to improve diagnostic accuracy and patient outcome. The purpose of this study was to determine the complementary diagnostic value of cardiac computed tomography angiography (CTA) to the

  6. Assessment of Coronary Artery Calcium on Low-Dose Coronary Computed Tomography Angiography With Iterative Reconstruction

    NARCIS (Netherlands)

    Braber, Thijs L; Willemink, Martin J; Bohté, Elzemiek H; Mosterd, Arend; Leiner, Tim; Velthuis, Birgitta K

    2016-01-01

    OBJECTIVE: This study aims to evaluate whether coronary calcium scoring (CCS) is also feasible using low-radiation-dose coronary computed tomography angiography (CCTA) in combination with iterative reconstruction. METHODS: Forty-three individuals without known coronary artery disease underwent both

  7. Atherosclerotic plaque burden in cocaine users with acute chest pain : Analysis by coronary computed tomography angiography

    NARCIS (Netherlands)

    Ebersberger, Ullrich; Sudarski, Sonja; Schoepf, U. Joseph; Bamberg, Fabian; Tricarico, Francesco; Apfaltrer, Paul; Blanke, Philipp; Schindler, Andreas; Makowski, Marcus R.; Headden, Gary F.; Leber, Alexander W.; Hoffmann, Ellen; Vliegenthart, Rozemarijn

    Chest pain associated with cocaine use represents an increasing problem in the emergency department (ED). Cocaine use has been linked to the acute coronary syndrome (ACS) and acute myocardial infarction (AMI). We used coronary computed tomography angiography (cCTA) to evaluate the prevalence,

  8. Post-mortem computed tomography angiography: past, present and future.

    Science.gov (United States)

    Saunders, Sarah L; Morgan, Bruno; Raj, Vimal; Rutty, Guy N

    2011-09-01

    The role of imaging has been long established in forensic practice as an adjunct to the conventional autopsy. Recently with the development of MDCT, there has been a large international push towards the development of the so called "near virtual autopsy." Currently a large obstacle to the acceptance of "near virtual autopsies" is the failure of post-mortem imaging to yield detailed information about the coronary arteries. This is a major deficiency of post-mortem MDCT and MRI compared to conventional autopsy as standard clinical angiography relies on circulation. One possible way to overcome this is by the use of post-mortem MDCT angiography. This review paper considers the past, current and future advances in cadaver cardiac imaging which, if successful, will take radiological imaging one step closer to the widespread introduction of near virtual autopsies.

  9. Induced apnea enhances image quality and visualization of cardiopulmonary anatomic during contrastenhanced cardiac computerized tomographic angiography in children.

    Science.gov (United States)

    Chakravarthy, Murali; Sunilkumar, Gubbihalli; Pargaonkar, Sumant; Hosur, Rajathadri; Harivelam, Chidananda; Kavaraganahalli, Deepak; Srinivasan, Pradeep

    2015-01-01

    The purpose of our study was to determine the effect of induced apnea on quality of cardiopulmonary structures during computerized tomographic (CT) angiography images in children with congenital heart diseases. Pediatric patients with congenital heart defects undergoing cardiac CT angiography at our facility in the past 3 years participated in this study. The earlier patients underwent cardiac CT angiography without induced apnea and while, later, apnea was induced in patients, which was followed by electrocardiogram gated cardiac CT angiography. General anesthesia was induced using sleep dose of intravenous propofol. After the initial check CT, on request by the radiologist, apnea was induced by the anesthesiologist by administering 1 mg/kg of intravenous suxamethonium. Soon after apnea ensued, the contrast was injected, and CT angiogram carried out. CT images in the "apnea group" were compared with those in "nonapnea group." After the completion of the procedure, the patients were mask ventilated with 100% oxygen till the spontaneous ventilation was restored. We studied 46 patients, of whom 36 with apnea and yet another 10 without. The quality of the image, visualization of structures such as cardiac wall, outflow tracts, lung field, aortopulmonary shunts, and coronary arteries were analyzed and subjected to statistical analysis (Mann-Whitney U, Fischer's exact test and Pearson's Chi-square test). In the induced apnea group, overall image quality was considered excellent in 89% (n = 33) of the studies, while in the "no apnea group," only 30% of studies were excellent. Absent or minimal motion artifacts were seen in a majority of the studies in apnea group (94%). In the nonapnea group, the respiratory and body motion artifacts were severe in 50%, moderate in 30%, and minimal in 20%, but they were significantly lesser in the apnea group. All the studied parameters were statistically significant in the apnea group in contrast to nonapnea group (P cardiac CT

  10. Induced apnea enhances image quality and visualization of cardiopulmonary anatomic during contrastenhanced cardiac computerized tomographic angiography in children

    Directory of Open Access Journals (Sweden)

    Murali Chakravarthy

    2015-01-01

    Full Text Available Objective: The purpose of our study was to determine the effect of induced apnea on quality of cardiopulmonary structures during computerized tomographic (CT angiography images in children with congenital heart diseases. Methods: Pediatric patients with congenital heart defects undergoing cardiac CT angiography at our facility in the past 3 years participated in this study. The earlier patients underwent cardiac CT angiography without induced apnea and while, later, apnea was induced in patients, which was followed by electrocardiogram gated cardiac CT angiography. General anesthesia was induced using sleep dose of intravenous propofol. After the initial check CT, on request by the radiologist, apnea was induced by the anesthesiologist by administering 1 mg/kg of intravenous suxamethonium. Soon after apnea ensued, the contrast was injected, and CT angiogram carried out. CT images in the "apnea group" were compared with those in "nonapnea group." After the completion of the procedure, the patients were mask ventilated with 100% oxygen till the spontaneous ventilation was restored. Results: We studied 46 patients, of whom 36 with apnea and yet another 10 without. The quality of the image, visualization of structures such as cardiac wall, outflow tracts, lung field, aortopulmonary shunts, and coronary arteries were analyzed and subjected to statistical analysis (Mann-Whitney U, Fischer′s exact test and Pearson′s Chi-square test. In the induced apnea group, overall image quality was considered excellent in 89% (n = 33 of the studies, while in the "no apnea group," only 30% of studies were excellent. Absent or minimal motion artifacts were seen in a majority of the studies in apnea group (94%. In the nonapnea group, the respiratory and body motion artifacts were severe in 50%, moderate in 30%, and minimal in 20%, but they were significantly lesser in the apnea group. All the studied parameters were statistically significant in the apnea group in

  11. Multislice computed tomography angiography findings of chronic small bowel volvulus with jejunal diverticulosis.

    Science.gov (United States)

    Li, Xiao-Bing; Guan, Wen-Xian; Gao, Yuan

    2010-07-01

    A volvulus, which is torsion of the bowel and its mesentery, is a medical emergency. Small bowel volvulus rarely occurs in adults, although it has been reported in the presence of small bowel diverticulum. Multislice computed tomography (CT) angiography, by demonstrating the mesenteric vessels, can be of help in the diagnosis of small bowel volvulus, especially when CT or gastrointestinal studies fail to show the diverticulum. We present the multislice CT angiography findings of a 64-year-old woman with chronic intermittent volvulus resulting from jejunal diverticulosis, surgically confirmed. To our knowledge, no similar case has been reported previously in the literature.

  12. Significance of computerized tomography and nasal cytology in the ...

    African Journals Online (AJOL)

    Ehab

    inflammatory products and mouth breathing might also cause increased water and heat loss in the lower airways thereby contributing to asthmatic symptoms8. This work is aimed at identifying the significance of computed tomography scanning, nasal cytology examination, and serum total IgE assay in the diagnosis of ...

  13. Emission computerized myocardial tomography with the 7-pinhole collimator

    Energy Technology Data Exchange (ETDEWEB)

    Sochor, H.; Pachinger, O.; Ogris, E.; Probst, P.; Joskowicz, G.; Kaindl, F. (Vienna Univ. (Austria). Kardiologische Klinik)

    1983-01-01

    89 patients (78 with coronary artery disease, 11 normals) were studied comparatively with Tl-201 planar myocardial scintigraphy and 7-pinhole emission tomography with a mobile gamma-camera. In 46 patients stress studies were performed, the other studies were performed as resting protocols. In 13 patients a correlation of scintigraphically determined infarct size calculated from the Tl-201 tomograms with CK and CK-MB values (maximum values) in the acute infarction period was performed. 17 patients having undergone intracoronary streptolysis were studied to investigate the effect of this intervention. In patients without previous myocardial infarction (n=35) sensitivity of 7-pinhole tomography was significantly superior over planar reading of images (83% for qualitative evaluation, 91% for quantitative analysis). In patients with previous myocardial infarction (n=26) comparative sensitivities were not significantly different, although slightly higher, neverthelesss the fraction of questionable findings was reduced from 9 to 4%, furthermore in 31% an additional information concerning size or localization could be obtained from the tomograms. Predictive diagnostic accuracy was highest for quantitative 7-pinhole tomography (91%) but not significantly different from qualitative tomography but higher than for planar imaging. Specificities of all methods were comparable. In patients during the acute phase of myocardial infarction a significant correlation (r = 0.76 for CK, r = 0.78 for CK-MB, p < 0.01) was obtained with enzymatic markers of infarct size. In the group after intracoronary streptolysis 7-pinhole tomography was able to demonstrate a quantitative reduction of thallium infarct size in patients after successful lysis (23.5% vs 48.7%, p < 0.01).

  14. Diagnostic performance of multidetector computed tomography for detecting aorto-ostial lesions compared with catheter coronary angiography: multidetector computed tomography coronary angiography is superior to catheter angiography in detection of aorto-ostial lesions.

    Science.gov (United States)

    Kantarci, Mecit; Ceviz, Naci; Sevimli, Serdar; Bayraktutan, Ummugulsum; Ceyhan, Elvan; Duran, Cihan; Karaman, Adem; Durur, Irmak; Okur, Adnan

    2007-01-01

    In this study, our goal is to determine the use of multidetector computed tomography (MDCT) in detection of aorto-ostial lesions. Thirty-three patients suspected to have aorto-ostial lesion by either catheter angiography (CA) or MDCT coronary angiography comprised our study population. In 19 patients (group 1), aorto-ostial lesion was suspected based on CA, then MDCT coronary angiography was performed. In the remaining 14 patients (group 2), aorto-ostial lesion diagnosis was made by MDCT coronary angiography, and then afterward, CA was performed. A cardiologist and a radiologist reevaluated both the CA and MDCT coronary angiography recordings of all patients and their consensus formed the diagnosis. We accepted this consensus diagnosis as our criterion standard because a universal criterion standard to compare CA and MDCT findings with is not available. Then, the previous diagnoses by CA and MDCT coronary angiography were compared with the consensus diagnoses. Finally, 26 patients were diagnosed with aorto-ostial lesion, whereas 5 patients were found not to have aorto-ostial lesions. Two patients were diagnosed with abnormal origination of a coronary artery. When the results were evaluated in terms of the presence of aorto-ostial lesion, MDCT coronary angiography correctly diagnosed all 26 patients, and in the 5 patients with normal ostium, MDCT coronary angiography finding was also normal. However, 7 of 26 patients with aorto-ostial lesion were reported to be normal by CA, and also 5 patients with normal ostia were reported to have aorto-ostial lesion by CA. That is, 12 of 33 patients were misdiagnosed by CA. Moreover, CA missed the abnormal origination of the coronary arteries in 2 patients. When the results were evaluated in terms of the degree of stenosis in 26 patients with aorto-ostial lesion; MDCT coronary angiography predicted the final diagnosis in all 26 patients correctly. However, CA predicted the final degree of stenosis only in 12 patients. Catheter

  15. MULTIMODALITY IMAGING OF TORPEDO MACULOPATHY WITH SWEPT-SOURCE, EN FACE OPTICAL COHERENCE TOMOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

    Science.gov (United States)

    Papastefanou, Vasilios P; Vázquez-Alfageme, Clara; Keane, Pearse A; Sagoo, Mandeep S

    2016-10-19

    Multimodality image analysis of two cases of torpedo maculopathy. Imaging with fundus photography, autofluorescence (AF), swept-source optical coherence tomography (OCT), en face OCT, and OCT angiography. The basal diameter of the torpedo lesions was 1 mm × 2 mm. One case had a satellite lesion. Autofluorescence indicated variable loss of signal. Swept-source OCT and en face OCT demonstrated fundus excavation, attenuation of nuclear layers and disruption of the outer plexiform layer, loss of photoreceptors and a subretinal cleft. In one case, Sattler layer appeared extended at the cleft. Optical coherence tomography angiography indicated loss of flow in deep retinal vessels and increased flow in choroidal vessels surrounding the cleft. Multimodal imaging findings of torpedo maculopathy include disruption of the deep retinal capillary network, expansion of Sattler layer, and increased signal around the subretinal cleft.

  16. [Paranasal sinusitis: study with conventional and spiral computerized tomography].

    Science.gov (United States)

    Sartoni Galloni, S; Burzi, M; Lipparini, M; Gigli, F; Burci, P; Stamati, R; Guidarelli, G

    1996-01-01

    This study was aimed at comparing the diagnostic value of conventional computed tomography (CCT) with that of spiral computed tomography (SCT) in sinonasal structures and ostiomeatal complex in thirty patients with inflammatory disease. Ten patients were examined with CCT (3-mm slice thickness, 120 kV, 100 mA, 2-s gantry rotation) and 20 were examined with SCT (3-mm slice thickness, 120 kV, 200 mA, 1-s gantry rotation and computed image reconstruction every 3 mm); table gain was 3 mm (Pitch 1) in 10 patients and 5 mm (Pitch 1.6) in the other 10 patients. With the latter study protocol, diagnostic image quality was the same as with the other two protocols. Moreover, examination time was reduced, with increased patients' comfort; the exposure dose and X-ray tube overload were also reduced, with increased system yield.

  17. Imaging results of multi-modal ultrasound computerized tomography system designed for breast diagnosis.

    Science.gov (United States)

    Opieliński, Krzysztof J; Pruchnicki, Piotr; Gudra, Tadeusz; Podgórski, Przemysław; Kurcz, Jacek; Kraśnicki, Tomasz; Sąsiadek, Marek; Majewski, Jarosław

    2015-12-01

    Nowadays, in the era of common computerization, transmission and reflection methods are intensively developed in addition to improving classical ultrasound methods (US) for imaging of tissue structure, in particular ultrasound transmission tomography UTT (analogous to computed tomography CT which uses X-rays) and reflection tomography URT (based on the synthetic aperture method used in radar imaging techniques). This paper presents and analyses the results of ultrasound transmission tomography imaging of the internal structure of the female breast biopsy phantom CIRS Model 052A and the results of the ultrasound reflection tomography imaging of a wire sample. Imaging was performed using a multi-modal ultrasound computerized tomography system developed with the participation of a private investor. The results were compared with the results of imaging obtained using dual energy CT, MR mammography and conventional US method. The obtained results indicate that the developed UTT and URT methods, after the acceleration of the scanning process, thus enabling in vivo examination, may be successfully used for detection and detailed characterization of breast lesions in women. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Coronary plaque quantification and fractional flow reserve by coronary computed tomography angiography identify ischaemia-causing lesions

    DEFF Research Database (Denmark)

    Gaur, Sara; Øvrehus, Kristian Altern; Dey, Damini

    2016-01-01

    tomography angiography (CTA)-derived fractional flow reserve (FFRCT), and lesion-specific ischaemia identified by FFR in a substudy of the NXT trial (Analysis of Coronary Blood Flow Using CT Angiography: Next Steps). METHODS AND RESULTS: Coronary CTA stenosis, plaque volumes, FFRCT, and FFR were assessed...

  19. EN FACE OPTICAL COHERENCE TOMOGRAPHY (OCT) AND OCT ANGIOGRAPHY FINDINGS IN RETINAL ASTROCYTIC HAMARTOMAS.

    Science.gov (United States)

    Despréaux, Raphaelle; Mrejen, Sarah; Quentel, Gabriel; Cohen, Salomon Y

    2017-01-01

    To report spectral-domain optical coherence tomography, en face optical coherence tomography (OCT), and optical coherence tomography angiography findings in retinal astrocytic hamartomas. Four cases of retinal astrocytic hamartomas, with small white or yellowish typical retinal mass, were imaged with fundus photography, intravenous fluorescein angiography, fundus autofluorescence, spectral-domain OCT, en face OCT, and OCT angiography. The tumor was solitary in all cases and involved the posterior pole. It was idiopathic in three cases and was related to tuberous sclerosis complex in one case. The OCT findings included intralesional lucencies in two cases with no exudation. The tumor was within the retinal nerve fiber layer or deeper, usually overlying the inner plexiform layer providing a protusion in the vitreous cavity. Vitreous changes were present in all cases, corresponding to thickening and adhesion of the vitreous facing the lesion (two cases), apparent interdigitation with vitreous (one case), and marked condensation of the vitreous with interdigitations (one case). En face OCT imaging at the level of the retinal pigment epithelial zone showed a hyporeflective, round, well-delineated mass. A peripheral poorly defined hyperreflectivity with a central hyporeflectivity was observed at the level of mid-retina, likely because of shadowing effect. The OCT-A reveals a dense vascular network within the tumor. Retinal astrocytic hamartomas may be well characterized by non-invasive imaging using spectral-domain OCT, en face OCT, and OCT angiography. The OCT angiography seemed to show tumor vascularity, which may represent dilated disorganized and anastomotic superficial and deep plexus capillaries. The tumor is often unique, peripapillary, small in diameter, and dome-shaped on spectral-domain OCT protruding into the vitreous cavity, responsible for vitreous changes facing the lesion.

  20. Fractional flow reserve derived from coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Eftekhari, Ashkan; Min, James; Achenbach, Stephan

    2016-01-01

    AIMS: Fractional flow reserve (FFR) derived from coronary computed tomography (FFRCT) has high diagnostic performance in stable coronary artery disease (CAD). The diagnostic performance of FFRCT in patients with hypertension (HTN) and diabetes (DM), who are at risk of microvascular impairment...... risk for microvascular disease....

  1. Calcification of all four parathyroid glands in a hemodialysis patient with secondary hyperparathyroidism revealed by computerized tomography.

    Science.gov (United States)

    Peces, R; Rodríguez, M; González, F; Ablanedo, P

    2001-09-01

    This report describes the parathyroid scan, computerized tomography and histologic findings in a young female hemodialysis patient with severe secondary hyperparathyroidism. These findings included hyperplasia and calcification of all four parathyroid glands.

  2. An Anatomical Study of Maxillary-Zygomatic Complex Using Three-Dimensional Computerized Tomography-Based Zygomatic Implantation

    National Research Council Canada - National Science Library

    2017-01-01

    Objective. To obtain anatomical data of maxillary-zygomatic complex based on simulating the zygomatic implantation using cadaver heads and three-dimensional computerized tomography (3D-CT). Methods...

  3. Whole body magnetic resonance angiography and computed tomography angiography in the vascular mapping of head and neck: an intraindividual comparison

    Science.gov (United States)

    2014-01-01

    Introduction The aim of the study was to compare the detectability of neck vessels with contrast enhanced magnetic resonance angiography (MRA) in the setting of a whole-body MRA and multislice computed tomography angiography (CTA) for preoperative vascular mapping of head and neck. Methods In 20 patients MRA was performed prior to microvascular reconstruction of the mandible with osteomyocutaneous flaps. CTA of the neck served as the method of reference. 1.5 T contrast enhanced magnetic resonance angiograms were acquired to visualize the vascular structures of the neck in the setting of a whole-body MRA examination. 64-slice spiral computed tomography was performed with a dual-phase protocol, using the arterial phase images for 3D CTA reconstruction. Maximum intensity projection was employed to visualize MRA and CTA data. To retrieve differences in the detectability of vessel branches between MRA and CTA, a McNemar test was performed. Results All angiograms were of diagnostic quality. There were no statistically significant differences between MRA and CTA for the detection of branches of the external carotid artery that are relevant host vessels for microsurgery (p = 0.118). CTA was superior to MRA if all the external carotid artery branches were included (p < 0.001). Conclusions MRA is a reliable alternative to CTA in vascular mapping of the cervical vasculature for planning of microvascular reconstruction of the mandible. In the setting of whole-body MRA it could serve as a radiation free one-stop-shop tool for preoperative assessment of the arterial system, potentially covering both, the donor and host site in one single examination. PMID:24884580

  4. Single-Photon Emission Computerized Tomography (SPECT in Neuropsychiatry: A Review

    Directory of Open Access Journals (Sweden)

    B. K. Puri

    1992-01-01

    Full Text Available Cranial single-photon emission computerized tomography (SPECT or SPET can now give regional cerebral blood flow images with a resolution approaching that of positron emission tomography (PET. In this paper, the use of high resolution SPECT neuroimaging in neuropsychiatric disorders, including Alzheimer's disease, multi-infarct dementia, Pick's disease, progressive supranuclear palsy, Korsakoff's psychosis, Creutzfeld-Jakob disease, Parkinson's disease, Huntington's disease, schizophrenia, mood disorders, obsessive–compulsive disorder, HIV infection and AIDS is reviewed. Finally, further potential research and clinical uses, based on ligand studies, are outlined.

  5. Patient and institutional characteristics associated with initial computerized tomography in children presenting to the emergency department with kidney stones.

    Science.gov (United States)

    Ziemba, Justin B; Canning, Douglas A; Lavelle, Jane; Kalmus, Angela; Tasian, Gregory E

    2015-05-01

    Professional associations recommend ultrasound as the initial imaging study in children with suspected nephrolithiasis but computerized tomography remains frequently used. We identified patient and institutional characteristics associated with computerized tomography as the first imaging study in children with nephrolithiasis diagnosed in the emergency department. We performed a cross-sectional study of children 2 to 18 years old with nephrolithiasis who were referred to a freestanding pediatric hospital from 2003 to 2012. We identified the imaging modality first used to evaluate the child. Medical directors at the emergency department where children were first evaluated were sent a questionnaire to ascertain emergency department characteristics. Multivariate hierarchical logistic regression models were used to determine patient and institutional characteristics associated with initial computerized tomography. Of 536 eligible children 323 (60.2%) were evaluated at emergency departments from which surveys were returned. Of the 323 children 238 (71%) underwent computerized tomography as initial imaging. Ultrasound was available at all emergency departments. Older patient age was associated with higher initial computerized tomography use (OR 1.09, 95% CI 1.04-1.16). A more recent year of diagnosis (OR 0.80, 95% CI 0.72-0.88) and a clinical care pathway that used ultrasound as initial imaging (OR 0.29, 95% CI 0.01-0.38) were associated with lower initial computerized tomography use. A clinical care pathway in the emergency department was the only institutional characteristic associated with lower computerized tomography use. Future studies are needed to determine whether care pathways using ultrasound for initial imaging in children with suspected nephrolithiasis would decrease inappropriate computerized tomography and improve adherence to national guidelines. Copyright © 2015. Published by Elsevier Inc.

  6. Diagnostic value of ultrasound, computed tomography, and angiography in ruptured aortic aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Landtman, M.; Kivisaari, L.; Bondestam, S.; Taavitsainen, M.; Standertskjoeld-Nordenstam, C.G.; Somer, K.

    1984-11-01

    Some ruptural aneurysms cause nonspecific symptoms and the patients are referred for radiological examination because of the problems of differential diagnosis from conditions such as renal colic, diverticulitis, herniated disc, aortic dissection etc. Seven such patients have been examined either with ultrasonography, computed tomography or angiography. The diagnostic methods are compared. The more recent US and CT imaging methods are sufficiently rapid and reliable for diagnostic purposes, which should improve the prognosis for patients requiring immediate surgery for ruptured aortic aneurysms.

  7. Current concepts and advances: computerized tomography in sports medicine.

    Science.gov (United States)

    Buckwalter, Kenneth A

    2009-03-01

    Computed tomography (CT) is a widely used imaging technique. With the introduction of multidetector row technology, CT has been further refined. Although the focus of this transformation has been body and cardiac imaging, orthopedic imaging has benefited greatly. Specifically, the improvements in CT have made it possible to obtain submillimeter-thick slices that enable the creation of high-resolution multiplanar reformations from a single scan. These images usually are indistinguishable from direct plane acquisitions and provide unparalleled detail. Additionally, the factors responsible for causing CT image artifacts when hardware is present are much better understood and the improvements in CT technique and technology can be exploited to provide better images of patients with orthopedic hardware. The detailed multiplanar visualization of joints facilitates CT arthrography that has undergone a renaissance. CT arthrography is useful in the very large athlete or patient, the claustrophobic, and for those patients who fail a conventional magnetic resonance examination or magnetic resonance arthrogram.

  8. Computed tomography coronary angiography with heart rate control premedication: a best practice implementation project.

    Science.gov (United States)

    Mander, Gordon Thomas Waterland

    2017-07-01

    Computed tomography coronary angiography patient preparation with heart rate control premedication is employed in departments across Australia. However, the methods of administration vary widely between institutions and do not always follow best practice. This aim of the study was to identify and promote best practice in the administration of heart rate premedication in computed tomography coronary angiography at a regional hospital in Australia. The Joanna Briggs Institute have validated audit and feedback tools to assist with best practice implementation projects. This project used these tools, which involve three phases of activity - a pre-implementation audit, reflecting on results and implementing strategies to address non-compliance, and a post-implementation audit to assess the outcomes. A baseline audit identified non-compliance in the majority of measured audit criteria. Following implementation of an institution-specific guideline and associated worksheet, improved compliance was shown across all audit criteria. Following the development and implementation of institution-specific evidence-based resources relating to heart rate control in computed tomography coronary angiography, a high level of compliance consistent with best practice was achieved.

  9. Post-mortem CT-coronary angiography

    DEFF Research Database (Denmark)

    Pøhlsgaard, Camilla; Leth, Peter Mygind

    2007-01-01

    post-mortem coronary angiography and computerized tomography.  We describe how to prepare and inject the contrast medium, and how to establish a CT-protocol that optimizes spatial resolution, low contrast resolution and noise level. Testing of the method on 6 hearts, showed that the lumen...

  10. MULTIMODAL IMAGING OF ACUTE EXUDATIVE POLYMORPHOUS VITELLIFORM MACULOPATHY WITH OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY AND ADAPTIVE OPTICS SCANNING LASER OPHTHALMOSCOPY.

    Science.gov (United States)

    Skondra, Dimitra; Nesper, Peter L; Fawzi, Amani A

    2017-05-16

    To report a case of acute exudative polymorphous vitelliform maculopathy including the findings of optical coherence tomography angiography and adaptive optics scanning laser ophthalmoscopy. Findings on clinical examination, color fundus photography, spectral-domain optical coherence tomography, infrared reflectance, autofluorescence, optical coherence tomography angiography, and adaptive optics scanning laser ophthalmoscopy. A 54-year-old white man with no significant medical history and history of smoking presented with bilateral multiple serous and vitelliform detachments consistent with acute exudative polymorphous vitelliform maculopathy. Extensive infectious, inflammatory, and malignancy workup was negative. Spectral-domain optical coherence tomography showed thickened, hyperreflective ellipsoid zone, subretinal fluid, and focal as well as diffuse subretinal hyperreflective material corresponding to the vitelliform lesions. Optical coherence tomography angiography showed normal retinal and choroidal vasculature, whereas adaptive optics scanning laser ophthalmoscopy showed circular focal "target" lesions at the level of the photoreceptors in the area of foveal detachment. Multimodal imaging is valuable in evaluating patients with acute exudative polymorphous vitelliform maculopathy.

  11. A computerized tomography system for transcranial ultrasound imaging.

    Science.gov (United States)

    Tang, Sai Chun; Clement, Gregory T

    Hardware for tomographic imaging presents both challenge and opportunity for simplification when compared with traditional pulse-echo imaging systems. Specifically, point diffraction tomography does not require simultaneous powering of elements, in theory allowing just a single transmit channel and a single receive channel to be coupled with a switching or multiplexing network. In our ongoing work on transcranial imaging, we have developed a 512-channel system designed to transmit and/or receive a high voltage signal from/to arbitrary elements of an imaging array. The overall design follows a hierarchy of modules including a software interface, microcontroller, pulse generator, pulse amplifier, high-voltage power converter, switching mother board, switching daughter board, receiver amplifier, analog-to-digital converter, peak detector, memory, and USB communication. Two pulse amplifiers are included, each capable of producing up to 400Vpp via power MOSFETS. Switching is based around mechanical relays that allow passage of 200V, while still achieving switching times of under 2ms, with an operating frequency ranging from below 100kHz to 10MHz. The system is demonstrated through ex vivo human skulls using 1MHz transducers. The overall system design is applicable to planned human studies in transcranial image acquisition, and may have additional tomographic applications for other materials necessitating a high signal output.

  12. Juvenile nasopharyngeal angiofibroma - study of the tumor extension and vascularization through computerized tomography (CT) scan and angiography and the patient's age; Nasoangiofibroma juvenil - estudo da extensao e vascularizacao do tumor pela tomografia computadorizada e angiografia, e da idade do paciente

    Energy Technology Data Exchange (ETDEWEB)

    Sennes, Luiz Ubirajara

    1997-07-01

    The juvenile nasopharyngeal angiofibroma is a rare benign tumor that affects male adolescents. It is a fibro-vascular tumor with an exuberant intra tumor blood flow and irrigated by several arteries. It originates from the lateral and posterior region of the nasal cavity and, due to its characteristic multidirectional growth, widely affects the paranasal sinuses and skull base, sometimes invading the cranial fossa or the cheek. The determinant factors of its growth and vascularisation are unknown. Attempting to clarify them, 33 patients from the University of Sao Paulo Medicine were studied from 1983 to 1995, with complete history and radiological documentation (CT scan and angiography), as well as with histological confirmation of the diagnosis. In order to take only tumors with natural evolution, patients with recidivant tumor and those already submitted to any previous treatment were excluded. The parameters evaluate were: patient age and tumor extension (by classification, degree of invasion and number of compromised sites in CT scan) and vascularisation (by number and degree of participation of bilateral arteries in angiography). The se data were tabled and correlated one with each other. (author)

  13. Parapapillary Choroidal Microvasculature Dropout in Glaucoma: A Comparison between Optical Coherence Tomography Angiography and Indocyanine Green Angiography.

    Science.gov (United States)

    Lee, Eun Ji; Lee, Kyoung Min; Lee, Seung Hyen; Kim, Tae-Woo

    2017-08-01

    To investigate whether the parapapillary choroidal microvasculature dropout (MvD) determined by optical coherence tomography angiography (OCTA) in glaucomatous eyes indicates a true perfusion defect and whether the MvD accurately represents the area of nonperfusion. Observational case series. Thirty primary open-angle glaucoma (POAG) patients with choroidal MvD as determined by OCTA and 13 POAG patients without this dropout. Peripapillary circulation was evaluated using both OCTA and indocyanine green angiography (ICGA). For OCTA, the choroidal microvasculature was evaluated using 4.5×4.5-mm choroid-disc vessel density maps of OCTA images of the optic nerve head. An MvD was identified in OCTA by the presence of a capillary dropout. A filling defect observed in ICGA was defined as a perfusion defect (ICGPD). The topographic correlations between MvD and ICGPD determined based on their circumferential extent, location, and area. The ICGPD was observed as a sectoral filling defect in the 30 POAG patients exhibiting MvD and appeared identical to the MvD in terms of the shape and location. The circumferential extent, location, and area of ICGPD did not differ from those of the MvD (all P > 0.05). The ICGPD was not found in any of the eyes not having the MvD. A localized MvD observed in the parapapillary choroid using OCTA coincided with the ICGPD detected by ICGA. These findings indicate that OCTA accurately images impaired parapapillary choroidal circulation. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  14. Morphologic features of focal choroidal excavation on spectral domain optical coherence tomography with simultaneous angiography.

    Science.gov (United States)

    Shinojima, Ari; Kawamura, Akiyuki; Mori, Ryusaburo; Yuzawa, Mitsuko

    2014-07-01

    To reveal clinically relevant morphologic findings in patients with focal choroidal excavation (FCE) using enhanced depth imaging optical coherence tomography. Thirty-one FCE lesions in 29 eyes of 26 patients (21 men, 23 eyes; 5 women, 6 eyes) were studies. In all 26 patients, color fundus photographs were obtained, and fluorescein angiography and indocyanine green angiography with simultaneous enhanced depth imaging optical coherence tomography were performed. Twenty-five eyes also underwent angiographic video recording. Focal choroidal excavation was detected in eyes with typical age-related macular degeneration, central serous chorioretinopathy, polypoidal choroidal vasculopathy, and idiopathic choroidal neovascularization, whereas in 8 eyes, FCE was considered to be idiopathic. Morphologically, FCE lesions were classified into 3 types: cone-shaped, bowl-shaped, and mixed. The cone-shaped type was detected in 17 lesions, bowl-shaped in 8, and mixed in 6, on optical coherence tomography findings. All bowl-shaped and mixed types had retinal pigment epithelial irregularities within the FCE lesion. The cone-shaped type was not observed in eyes with typical age-related macular degeneration. Morphologically, FCE lesions were classified into cone-shaped, bowl-shaped, and mixed types, based on optical coherence tomography findings. Focal choroidal excavation formation may be associated in part with chorioretinal diseases such as age-related macular degeneration and central serous chorioretinopathy, whereas some eyes are considered to have idiopathic FCE.

  15. Post-mortem computed tomography (PMCT and PMCT-angiography after transvascular cardiac intervention

    Directory of Open Access Journals (Sweden)

    Beatrice Vogel

    2014-10-01

    Full Text Available Background and Purpose: During the last years, Post Mortem Computed Tomography (PMCT has become an integral part of the autopsy. PMCT-angiography may augment PMCT. Both exams have proven their value in visualizing complications after heart surgery. Therefore, they should also show complications after transvascular interventions. This assumption initiated our project: to evaluate the possibilities of PMCT and PMCT-angiography after transvascular cardiac interventions. Material and Methods: In our archives of characteristic and typical PMCT findings, we searched for observations on preceding transvascular cardiac interventions. Additionally, we reviewed our PMCTangiographies (N=140. Results: After transvascular cardiac interventions, PMCT and PMCT-angiography visualized bleeding, its amount and its origin, cardiac tamponade, free and covered perforations, transvascular implanted valves and their position, catheters and pacemakers with fractures, abnormal loops and bending. Bubbles in the coronary vessels (indicating air embolism become visible. Conclusion: After transvascular cardiac interventions, PMCT and PMCT-angiography show complications and causes of death. They prove a correct interventional approach and also guide autopsy. In isolated cases, they may even replace autopsy.

  16. Intravenous flat-detector computed tomography angiography for high-grade carotid stenosis.

    Science.gov (United States)

    Jeon, Jin Sue; Sheen, Seung Hun; Kim, Heung Cheol

    2013-01-01

    The significant feature of intravenous flat-detector computed tomography (IV FDCT) angiography is its role in neurointerventional setting without patient transfer. However, few studies have addressed the accuracy of IV FDCT in estimating carotid stenosis and length. This study examined the reliability of IV FDCT in the diagnosis of high-grade carotid stenosis and stenosis length with digital subtraction angiography (DSA) as the reference. Intravenous flat-detector CT and DSA were conducted simultaneously for 33 patients with 42 stenosed carotid arteries who were suspected of having symptomatic high-grade stenosis by carotid duplex ultrasound, magnetic resonance angiography, or CT angiography. The degree of stenosis and length discrepancy between 2 tests were recorded by 2 readers. The intraobserver and interobserver agreements were excellent for measuring high-grade carotid stenosis (κ = 0.87 and 0.82). Intravenous flat-detector CT had a sensitivity of 96.3%, specificity of 93.3%, and negative predictive value of 93.3% for detecting high-grade stenosis (≥70%) compared with DSA. Bland-Altman plots demonstrated excellent correlation of the degree of stenosis IV FDCT with DSA. Length discrepancy (IV FDCT - DSA, in millimeters) did not differ significantly according to degree of stenosis (Spearman rank test; r = 0.18, P = 0.26). Intravenous flat-detector CT can be a feasible and time-saving test for evaluating high-grade carotid stenosis and stenosis length.

  17. SPECTRAL DOMAIN VERSUS SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF THE RETINAL CAPILLARY PLEXUSES IN SICKLE CELL MACULOPATHY.

    Science.gov (United States)

    Jung, Jesse J; Chen, Michael H; Frambach, Caroline R; Rofagha, Soraya; Lee, Scott S

    2016-10-05

    To compare the spectral domain and swept source optical coherence tomography angiography findings in two cases of sickle cell maculopathy. A 53-year-old man and a 24-year-old man both with sickle cell disease (hemoglobin SS) presented with no visual complaints; Humphrey visual field testing demonstrated asymptomatic paracentral scotomas that extended nasally in the involved eyes. Clinical examination and multimodal imaging including spectral domain and swept source optical coherence tomography, and spectral domain optical coherence tomography angiography and swept source optical coherence tomography angiography (Carl Zeiss Meditec Inc, Dublin, CA) were performed. Fundus examination of both patients revealed subtle thinning of the macula. En-face swept source optical coherence tomography confirmed the extent of the thinning correlating with the functional paracentral scotomas on Humphrey visual field. Swept source optical coherence tomography B-scan revealed multiple confluent areas of inner nuclear thinning and significant temporal retinal atrophy. En-face 6 × 6-mm spectral domain optical coherence tomography angiography of the macula demonstrated greater loss of the deep capillary plexus compared with the superficial capillary plexus. Swept source optical coherence tomography angiography 12 × 12-mm imaging captured the same macular findings and loss of both plexuses temporally outside the macula. In these two cases of sickle cell maculopathy, deep capillary plexus ischemia is more extensive within the macula, whereas both the superficial capillary plexus and deep capillary plexus are involved outside the macula likely due to the greater oxygen demands and watershed nature of these areas. Swept source optical coherence tomography angiography clearly demonstrates the angiographic extent of the disease correlating with the Humphrey visual field scotomas and confluent areas of inner nuclear atrophy.

  18. Evaluation of the absorbed dose in odontological computerized tomography; Avaliacao da dose absorvida em tomografia computadorizada odontologica

    Energy Technology Data Exchange (ETDEWEB)

    Legnani, Adriano; Schelin, Hugo R.; Rocha, Anna Silvia P.S. da, E-mail: schelin@utfpr.edu.b, E-mail: anna@utfpr.edu.b [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Khoury, Helen J., E-mail: khoury@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2011-10-26

    This paper evaluated the absorbed dose at the surface entry known as 'cone beam computed tomography' (CBCT) in odontological computerized tomography. Examination were simulated with CBCT for measurements of dose. A phantom were filled with water, becoming scatter object of radiation. Thermoluminescent dosemeters were positioned on points correspondent to eyes and salivary glands

  19. 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 ( ...

  20. Co-registration of optical coherence tomography and X-ray angiography in percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Hebsgaard, Lasse; Nielsen, Troels Munck; Tu, Shengxian

    2014-01-01

    Background Intracoronary imaging provides accurate lesion delineation and precise measurements for sizing and positioning of coronary stents. During percutaneous coronary intervention (PCI), it may be challenging to identify corresponding segments between intracoronary imaging and angiography....... Computer based online co-registration may aid the target segment identification. Methods The DOCTOR fusion study was a prospective, single arm, observational study including patients admitted for elective PCI. Optical coherence tomography (OCT) was acquired pre-stent implantation for sizing of stents...... to the computer-based co-registration, segments of the target lesion indicated on OCT were left uncovered by stent in 14 patients (70%). Conclusion Computer based online co-registration of OCT and angiography is feasible. Frequent inaccuracies in operator based registration indicate that computer aided co...

  1. Noninvasive Assessment of Coronary Artery Disease: Fractional Flow Reserved Derived from Coronary Computed Tomography Angiography (FFRCT

    Directory of Open Access Journals (Sweden)

    Rațiu Mihaela

    2016-09-01

    Full Text Available Invasive coronary angiography (ICA completed by fractional flow reserve (FFR assessment represents the main procedure that is performed in the decision process for coronary revascularization. Coronary Computed Tomography Angiography (CCTA is an effective method used in the noninvasive anatomic assessment of coronary artery disease (CAD. However, CCTA tends to overestimate and does not offer hemodynamic data about the coronary lesions. Recent progresses made in the research involving computational fluid dynamics and image modeling permit the evaluation of FFRCT noninvasively, using data obtained in a standard CCTA. Studies have shown an improved precision and discrimination of FFRCT compared to CCTA for the diagnosis of significant coronary artery stenosis. In this review, we aimed to summarize the role of CCTA in CAD evaluation, the impact of FFRCT, the scientific basis of this novel method and its potential clinical applications.

  2. Optical Coherence Tomography Angiography Findings in Dengue-Related Maculopathy: A Case Report.

    Science.gov (United States)

    Tavassoli, Shokufeh; Carreño, Ester; Teoh, Stephen C; Theodoropoulou, Sofia; Bailey, Clare; Lee, Richard W J; Dick, Andrew D

    2016-11-01

    The ophthalmic manifestations of dengue fever include a visually impairing maculopathy, where patients are left with a central or paracentral relative scotoma. The authors present a case of a 26-year-old female patient returning from Thailand with unilateral reduction in visual acuity and a central scotoma associated with dengue fever. The authors report the use of the optical coherence tomography angiography (OCTA) as a noninvasive imaging platform to demonstrate its value in showing the persistent changes corresponding to the functional central scotoma in dengue-related maculopathy, which often cannot be visualized clinically or by standard OCT and fundus fluorescein angiography. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:1057-1060.]. Copyright 2016, SLACK Incorporated.

  3. Intravenous Flat-Detector Computed Tomography Angiography for Symptomatic Cerebral Vasospasm following Aneurysmal Subarachnoid Hemorrhage

    Directory of Open Access Journals (Sweden)

    Jin Pyeong Jeon

    2014-01-01

    Full Text Available The study evaluated the diagnostic accuracy of intravenous flat-detector computed tomography (IV FDCT angiography in assessing hemodynamically significant cerebral vasospasm in patients with subarachnoid hemorrhage (SAH with digital subtraction angiography (DSA as the reference. DSA and IV FDCT were conducted concurrently in patients suspected of having symptomatic cerebral vasospasm postoperatively. The presence and severity of vasospasm were estimated according to location (proximal versus distal. Vasospasm >50% was defined as having hemodynamic significance. Vasospasms 50% with DSA as the reference. Bland-Altman plots revealed good agreement of assessing vasospasm between the two tests. The discrepancy of vasospasm severity was more noted in the distal location with high-severity. However, it was not statistically significant (Spearman’s rank test; r=0.15, P=0.35. Therefore, IV FDCT could be a feasible noninvasive test to evaluate suspected significant vasospasm in SAH.

  4. 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.

  5. Study on beam geometry and image reconstruction algorithm in fast neutron computerized tomography at NECTAR facility

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J. [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China); Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, Garching 80748 (Germany); Buecherl, T. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, Garching 80748 (Germany); Zou, Y., E-mail: zouyubin@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China); Guo, Z. [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China)

    2011-09-21

    Investigations on the fast neutron beam geometry for the NECTAR facility are presented. The results of MCNP simulations and experimental measurements of the beam distributions at NECTAR are compared. Boltzmann functions are used to describe the beam profile in the detection plane assuming the area source to be set up of large number of single neutron point sources. An iterative algebraic reconstruction algorithm is developed, realized and verified by both simulated and measured projection data. The feasibility for improved reconstruction in fast neutron computerized tomography at the NECTAR facility is demonstrated.

  6. Karyotype, Pedigree and cone-beam computerized tomography analysis of a case of nonsyndromic pandental anomalies.

    Science.gov (United States)

    Dharmani, Umesh; Jadhav, Ganesh Ranganath; Kaur Dharmani, Charan Kamal; Rajput, Akhil; Mittal, Priya; Abraham, Sathish; Soni, Vinay

    2015-01-01

    This case report presented a karyotype and pedigree analysis of a case with unusual combination of dental anomalies: Generalized short roots, talon cusps, dens invagination, low alveolar bone heights, very prominent cusp of carabelli and protostylid on first permanent molars, taurodontism of second permanent molars, rotated, missing and impacted teeth. None of the anomalies alone are rare. However, until date, nonsyndromic pandental anomalies that are affecting entire dentition with detailed karyotype, pedigree and cone-beam computerized tomography analysis have not been reported. The occurrence of these anomalies is probably incidental as the conditions are etiologically unrelated.

  7. Detection of drugs and explosives using neutron computerized tomography and artificial intelligence techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, F.J.O. [Instituto de Engenharia Nuclear, Cidade Universitaria, Rio de Janeiro, CEP 21945-970, Caixa Postal 68550 (Brazil)], E-mail: fferreira@ien.gov.br; Crispim, V.R.; Silva, A.X. [DNC/Poli, PEN COPPE CT, UFRJ Universidade Federal do Rio de Janeiro, CEP 21941-972, Caixa Postal 68509, Rio de Janeiro (Brazil)

    2010-06-15

    In this study the development of a methodology to detect illicit drugs and plastic explosives is described with the objective of being applied in the realm of public security. For this end, non-destructive assay with neutrons was used and the technique applied was the real time neutron radiography together with computerized tomography. The system is endowed with automatic responses based upon the application of an artificial intelligence technique. In previous tests using real samples, the system proved capable of identifying 97% of the inspected materials.

  8. Detection of drugs and explosives using neutron computerized tomography and artificial intelligence techniques.

    Science.gov (United States)

    Ferreira, F J O; Crispim, V R; Silva, A X

    2010-06-01

    In this study the development of a methodology to detect illicit drugs and plastic explosives is described with the objective of being applied in the realm of public security. For this end, non-destructive assay with neutrons was used and the technique applied was the real time neutron radiography together with computerized tomography. The system is endowed with automatic responses based upon the application of an artificial intelligence technique. In previous tests using real samples, the system proved capable of identifying 97% of the inspected materials. Copyright 2010 Elsevier Ltd. All rights reserved.

  9. Karyotype, Pedigree and cone-beam computerized tomography analysis of a case of nonsyndromic pandental anomalies

    Science.gov (United States)

    Dharmani, Umesh; Jadhav, Ganesh Ranganath; Kaur Dharmani, Charan Kamal; Rajput, Akhil; Mittal, Priya; Abraham, Sathish; Soni, Vinay

    2015-01-01

    This case report presented a karyotype and pedigree analysis of a case with unusual combination of dental anomalies: Generalized short roots, talon cusps, dens invagination, low alveolar bone heights, very prominent cusp of carabelli and protostylid on first permanent molars, taurodontism of second permanent molars, rotated, missing and impacted teeth. None of the anomalies alone are rare. However, until date, nonsyndromic pandental anomalies that are affecting entire dentition with detailed karyotype, pedigree and cone-beam computerized tomography analysis have not been reported. The occurrence of these anomalies is probably incidental as the conditions are etiologically unrelated. PMID:26283856

  10. Swept-Source Optical Coherence Tomography Angiography Findings in Torpedo Maculopathy.

    Science.gov (United States)

    Ali, Zaria; Shields, Carol Lally; Jasani, Kirti; Aslam, Tariq Mehmood; Balaskas, Konstantinos

    2017-11-01

    Torpedo maculopathy is a rare congenital anomaly of the retinal pigment epithelium (RPE). Various imaging modalities have been used to assess cases of torpedo maculopathy, including optical coherence tomography (OCT) and fundus autofluorescence (FAF). OCT angiography (OCTA) offers combined structural and flow characteristics of imaged lesions. The authors present OCTA findings in two cases of torpedo maculopathy. Common features include loss of RPE and choriocapillaris allowing greater visualization of larger vessels in the outer choroid. This confirms the potential of OCTA to provide greater detail of retinal and choroidal architecture and elucidate the histopathology of retino-choridal lesions. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:932-935.]. Copyright 2017, SLACK Incorporated.

  11. Small Bowel Imaging: Computed Tomography Enterography, Magnetic Resonance Enterography, Angiography, and Nuclear Medicine.

    Science.gov (United States)

    Fidler, Jeff L; Goenka, Ajit H; Fleming, Chad J; Andrews, James C

    2017-01-01

    Radiology examinations play a major role in the diagnosis, management, and surveillance of small bowel diseases and are complementary to endoscopic techniques. Computed tomography enterography and magnetic resonance enterography are the cross-sectional imaging studies of choice for many small bowel diseases. Angiography still plays an important role for catheter-directed therapies. With the emergence of hybrid imaging techniques, radionuclide imaging has shown promise for the evaluation of small bowel bleeding and Crohn disease and may play a larger role in the future. This article reviews recent advances in technology, diagnosis, and therapeutic options for selected small bowel disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Optical coherence tomography angiography: Technical principles and clinical applications in ophthalmology

    Science.gov (United States)

    Hagag, Ahmed M.; Gao, Simon S.; Jia, Yali; Huang, David

    2017-01-01

    Optical coherence tomography angiography (OCTA) is a functional extension of OCT that provides information on retinal and choroidal circulations without the need for dye injections. With the recent development of high-speed OCT systems and efficient algorithms, OCTA has become clinically feasible. In this review article, we discuss the technical principles of OCTA, including image processing and artifacts, and its clinical applications in ophthalmology. We summarize recent studies which qualitatively or quantitatively assess disease presentation, progression, and/or response to treatment. PMID:28966909

  13. Optical Coherence Tomography Angiography of Paracentral Acute Middle Maculopathy Associated With Primary Antiphospholipid Syndrome.

    Science.gov (United States)

    Trese, Matthew G J; Thanos, Aristomenis; Yonekawa, Yoshihiro; Randhawa, Sandeep

    2017-02-01

    The authors present the first case of paracentral acute middle maculopathy as a manifestation of primary antiphospholipid syndrome (APS) with multimodal imaging, including optical coherence tomography angiography (OCTA). The association between APS and ophthalmic sequela is well-known. Recent advances in multimodal imaging, specifically OCTA, allow for better characterization of the mechanism and extent by which retinal arterial thrombosis can cause vision loss. Using advanced imaging modalities, the authors provide a comprehensive assessment of retinal ischemia, which showed not only localized capillary occlusion, but also ischemia of the deep retinal capillary plexus. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:175-178.]. Copyright 2017, SLACK Incorporated.

  14. Non-Coronary Cardiac Findings and Pitfalls in Coronary Computed Tomography Angiography

    Directory of Open Access Journals (Sweden)

    Noriko Oyama-Manabe

    2011-01-01

    Full Text Available Non-coronary incidental findings are not rare. Kirsch et al found 67% non-coronary abnormalities with coronary computed tomography angiography (CCTA. Radiologists are expected to identify the extracoronary, intra- and para-cardiac anatomical structures and distinguish them from pathologic processes in CCTA. We have reviewed 2000 CCTA studies done at our institution with 64-MDCT. This pictorial essay presents case studies of non-atherosclerotic cardiovascular findings to recognize cardiac anatomic structures and how to distinguish them from pathologic processes. Correct interpretation of benign, clinically insignificant findings is crucial to avoid unnecessary additional imaging tests.

  15. Influence of Adaptive Statistical Iterative Reconstruction on coronary plaque analysis in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Kitslaar, Pieter H; Broersen, Alexander

    2016-01-01

    PURPOSE: The purpose of this study was to study the effect of iterative reconstruction (IR) software on quantitative plaque measurements in coronary computed tomography angiography (CCTA). METHODS: Thirty patients with a three clinical risk factors for coronary artery disease (CAD) had one CCTA...... performed. Images were reconstructed using FBP, 30% and 60% adaptive statistical IR (ASIR). Coronary plaque analysis was performed as per patient and per vessel (LM, LAD, CX and RCA) measurements. Lumen and vessel volumes and plaque burden measurements were based on automatic detected contours in each...

  16. Contrast Enhanced Ultrasound can Replace Computed Tomography Angiography for Surveillance After Endovascular Aortic Aneurysm Repair

    DEFF Research Database (Denmark)

    Bredahl, K; Taudorf, M; Lönn, L

    2016-01-01

    OBJECTIVE/BACKGROUND: Surveillance after endovascular aortic aneurysm repair (EVAR) is mandatory and computed tomography angiography (CTA) is considered the standard imaging modality, although patients are exposed to ionizing radiation and nephrotoxic contrast medium. The primary aim of this study...... August 2011 and 31 October 2014 were prospectively and consecutively enrolled. CEUS was added to the existing surveillance protocol, which included DUS, plain abdominal X-ray, and CTA at 3 and 12 months after stent implantation. RESULTS: In 278 patients, endoleaks were detected in 68, 69, and 46 cases...

  17. Optical coherence tomography angiography features of bilateral retinopathy associated with Chikungunya fever.

    Science.gov (United States)

    Agarwal, Aniruddha; Choudhary, Tripti; Gupta, Vishali

    2018-01-01

    A 66-year-old male patient presented with decreased vision in both eyes following episode of Chikungunya fever. Examination revealed bilateral retinal lesions with stippled pigmentary changes at the level of the choriocapillaris, involving the macula in the left eye. The retinopathy consisted of outer retinal disruption and retinochoroidal flow abnormalities detected using with additional imaging, including spectral-domain optical coherence tomography (OCT), autofluorescence, and OCT angiography (OCTA). The index case report describes unique OCTA findings in both eyes of an elderly male secondary to Chikungunya fever. Using the technique of OCTA, insights into the mechanisms of visual damage in viral retinopathies such as Chikungunya fever can be understood.

  18. Scalable wide-field optical coherence tomography-based angiography for in vivo imaging applications.

    Science.gov (United States)

    Xu, Jingjiang; Wei, Wei; Song, Shaozhen; Qi, Xiaoli; Wang, Ruikang K

    2016-05-01

    Recent advances in optical coherence tomography (OCT)-based angiography have demonstrated a variety of biomedical applications in the diagnosis and therapeutic monitoring of diseases with vascular involvement. While promising, its imaging field of view (FOV) is however still limited (typically less than 9 mm(2)), which somehow slows down its clinical acceptance. In this paper, we report a high-speed spectral-domain OCT operating at 1310 nm to enable wide FOV up to 750 mm(2). Using optical microangiography (OMAG) algorithm, we are able to map vascular networks within living biological tissues. Thanks to 2,048 pixel-array line scan InGaAs camera operating at 147 kHz scan rate, the system delivers a ranging depth of ~7.5 mm and provides wide-field OCT-based angiography at a single data acquisition. We implement two imaging modes (i.e., wide-field mode and high-resolution mode) in the OCT system, which gives highly scalable FOV with flexible lateral resolution. We demonstrate scalable wide-field vascular imaging for multiple finger nail beds in human and whole brain in mice with skull left intact at a single 3D scan, promising new opportunities for wide-field OCT-based angiography for many clinical applications.

  19. The Basilar Artery on Computed Tomography Angiography Prognostic Score for Basilar Artery Occlusion.

    Science.gov (United States)

    Alemseged, Fana; Shah, Darshan G; Diomedi, Marina; Sallustio, Fabrizio; Bivard, Andrew; Sharma, Gagan; Mitchell, Peter J; Dowling, Richard J; Bush, Steven; Yan, Bernard; Caltagirone, Carlo; Floris, Roberto; Parsons, Mark W; Levi, Christopher R; Davis, Stephen M; Campbell, Bruce C V

    2017-03-01

    Basilar artery occlusion is associated with high risk of disability and mortality. This study aimed to assess the prognostic value of a new radiological score: the Basilar Artery on Computed Tomography Angiography (BATMAN) score. A retrospective analysis of consecutive stroke patients with basilar artery occlusion diagnosed on computed tomographic angiography was performed. BATMAN score is a 10-point computed tomographic angiography-based grading system which incorporates thrombus burden and the presence of collaterals. Reliability was assessed with intraclass coefficient correlation. Good outcome was defined as modified Rankin Scale score of ≤3 at 3 months and successful reperfusion as thrombolysis in cerebral infarction 2b-3. BATMAN score was externally validated and compared with the Posterior Circulation Collateral score. The derivation cohort included 83 patients with 41 in the validation cohort. In receiver operating characteristic (ROC) analysis, BATMAN score had an area under receiver operating characteristic curve of 0.81 (95% confidence interval [CI], 0.7-0.9) in derivation cohort and an area under receiver operating characteristic curve of 0.74 (95% CI, 0.6-0.9) in validation cohort. In logistic regression adjusted for age and clinical severity, BATMAN score of BATMAN score of BATMAN score had greater accuracy compared with Posterior Circulation Collateral score ( P =0.04). The addition of collateral quality to clot burden in BATMAN score seems to improve prognostic accuracy in basilar artery occlusion patients. © 2017 American Heart Association, Inc.

  20. Sublingual Nitroglycerin Administration in Coronary Computed Tomography Angiography: a Systematic Review.

    Science.gov (United States)

    Takx, Richard A P; Suchá, Dominika; Park, Jakob; Leiner, Tim; Hoffmann, Udo

    2015-12-01

    To systematically investigate the literature for the influence of sublingual nitroglycerin administration on coronary diameter, the number of evaluable segments, image quality, heart rate and blood pressure, and diagnostic accuracy of coronary computed tomography (CT) angiography. A systematic search was performed in PubMed, EMBASE and Web of Science. The studies were evaluated for the effect of sublingual nitroglycerin on coronary artery diameter, evaluable segments, objective and subjective image quality, systemic physiological effects and diagnostic accuracy. Due to the heterogeneous reporting of outcome measures, a narrative synthesis was applied. Of the 217 studies identified, nine met the inclusion criteria: seven reported on the effect of nitroglycerin on coronary artery diameter, six on evaluable segments, four on image quality, five on systemic physiological effects and two on diagnostic accuracy. Sublingual nitroglycerin administration resulted in an improved evaluation of more coronary segments, in particular, in smaller coronary branches, better image quality and improved diagnostic accuracy. Side effects were mild and were alleviated without medical intervention. Sublingual nitroglycerin improves the coronary diameter, the number of assessable segments, image quality and diagnostic accuracy of coronary CT angiography without major side effects or systemic physiological changes. • Sublingual nitroglycerin administration results in significant coronary artery dilatation. • Nitroglycerin increases the number of evaluable coronary branches. • Image quality is improved the most in smaller coronary branches. • Nitroglycerin increases the diagnostic accuracy of coronary CT angiography. • Most side effects are mild and do not require medical intervention.

  1. Features of the choriocapillaris in myopic maculopathy identified by optical coherence tomography angiography.

    Science.gov (United States)

    Sayanagi, Kaori; Ikuno, Yasushi; Uematsu, Sato; Nishida, Kohji

    2017-11-01

    To describe the choriocapillaris features imaged by optical coherence tomography angiography (OCTA) in eyes with myopic maculopathy. In this retrospective, non-invasive, observational case series, 26 eyes with myopic maculopathy and 12 age-matched healthy eyes underwent fluorescein angiography, indocyanine green angiography (ICGA) (highly myopic eyes only), OCT and OCTA, and the choriocapillaris features seen on OCTA and ICGA were compared. In all five (19%) eyes with patchy atrophy of the 26 highly myopic eyes, OCTA showed complete loss of the choriocapillaris and large choroidal vessels in the atrophic area. In nine (35%) eyes with diffuse atrophy in the atrophic area, OCTA showed low-density choriocapillaris in all eyes and medium and large choroidal vessels in seven (78%) eyes. In 23 eyes (88%) with lacquer cracks, OCTA showed partial loss of the choriocapillaris in 22 (96%) eyes in the area of the lacquer cracks. OCTA could not visualise the full length of the lacquer cracks in any eyes compared with ICGA. OCTA visualised the choriocapillaris clearly. The choriocapillaris features differed depending to the category of myopic maculopathy. In eyes with lacquer cracks, choriocapillaris rupture might be less advanced than the breaks in Bruch's membrane and retinal pigment epithelium. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Diagnostic Performance of Coronary Computed Tomography Angiography and Myocardial Perfusion Imaging in Kidney Transplantation Candidates

    DEFF Research Database (Denmark)

    Winther, Simon; Svensson, My; Jørgensen, Hanne Mari Skou

    2015-01-01

    Abstract Objectives The goal of this study was to compare the diagnostic accuracy of the coronary artery calcium score (CACS), coronary computed tomography angiography (CTA), single-photon emission computed tomography (SPECT), and a combination of these tools in the diagnosis of obstructive...... that established noninvasive stress tests have low diagnostic accuracy, while the diagnostic performance of coronary CTA remains unknown. Methods We prospectively studied 138 patients referred for pre-transplant cardiac evaluation (mean age 54 years; age range 22 to 72 years; 68% male; 43% treated with dialysis......% for SPECT, 40% for Hybrid (CACS/SPECT), and 75% for Hybrid (coronary CTA/SPECT). Conclusions Coronary CTA is a reliable test with high sensitivity and a high negative predictive value for diagnosing obstructive CAD before kidney transplantation. A noninvasive approach with use of either coronary CTA...

  3. The accuracy and diagnostic yield of computerized tomography guided stereotactic biopsy in brain lesions.

    Science.gov (United States)

    Calişaneller, Tarkan; Ozdemir, Ozgür; Ozger, Ozkan; Ozen, Ozlem; Kiyici, Halil; Caner, Hakan; Altinörs, Nur

    2008-01-01

    Radiological imaging techniques provide early detection of neurological diseases but they do not always provide an adequate and reliable diagnosis. With the help of stereotactic biopsy techniques, it is possible to access brain lesions safely and with high precision. We described the surgical method used in our clinic and discussed our results with the help of the current literature. Ninety-four patients underwent computerized tomography-guided stereotactic brain biopsy in our clinic. Anatomical locations, diagnostic yield and accuracy of the procedure, morbidity and mortality rates were analyzed. A total of 100 stereotactic surgery procedures were performed on 94 patients. The localizations of the lesions were 13.83% frontal, 21.27% temporal, 27.66% parietal, 4.25% occipital, 4.25% multiple, 27.66% deep seated and 1.06% suprasellar. The histopathological diagnoses were 61.71% neuro-epithelial tumors, 8.51% metastases and 10.64% infectious lesions. Diagnostic yield was 86.16% and the accuracy was 90% in our series. Computerized tomography-guided stereotactic brain biopsy is a reliable and safe method. Main diagnostic problems in SBB are tissue heterogeneity, insufficient material and sampling error. These problems can be minimized by careful correlation of clinical, radiological and histopathological findings by an experienced team and by using modern technologies.

  4. The role of computerized tomography in the evaluation of gastrointestinal bleeding following negative or failed endoscopy: a review of current status.

    Science.gov (United States)

    Stunell, H; Buckley, O; Lyburn, I D; McGann, G; Farrell, M; Torreggiani, W C

    2008-01-01

    Gastrointestinal bleeding remains an important cause for emergency hospital admission with a significant related morbidity and mortality. Bleeding may relate to the upper or lower gastrointestinal tracts and clinical history and examination may guide investigations to the more likely source of bleeding. The now widespread availability of endoscopic equipment has made a huge impact on the rapid identification of the bleeding source. However, there remains a large group of patients with negative or failed endoscopy, in whom additional techniques are required to identify the source of bleeding. In the past, catheter angiography and radionuclide red cell labeling techniques were the preferred 'next step' modalities used to aid in identifying a bleeding source within the gastrointestinal tract. However, these techniques are time-consuming and of limited sensitivity and specificity. In addition, catheter angiography is a relatively invasive procedure. In recent years, computerized tomography (CT) has undergone major technological advances in its speed, resolution, multiplanar techniques and angiographic abilities. It has allowed excellent visualization of the both the small and large bowel allowing precise anatomical visualization of many causes of gastrointestinal tract (GIT) bleeding. In addition, recent advances in multiphasic imaging now allow direct visualization of bleeding into the bowel. In many centers CT has therefore become the 'next step' technique in identifying a bleeding source within the GIT following negative or failed endoscopy in the acute setting. In this review article, we review the current literature and discuss the current status of CT as a modality in investigating the patient with GIT bleeding.

  5. Optical Coherence Tomography Angiography: Employing a Novel Technique for Investigation in Vogt-Koyanagi-Harada Disease

    Directory of Open Access Journals (Sweden)

    Panagiotis Giannakouras

    2017-07-01

    Full Text Available Purpose: To report a case of Vogt-Koyanagi-Harada (VKH disease and describe the imaging findings by means of optical coherence tomography angiography (OCTA. Methods: Medical and ophthalmological history, ophthalmological examination, laboratory evaluation, B-scan ultrasonography, fluorescein and indocyanine angiography, and optical coherence tomography (OCT were performed at baseline, as well as OCTA. Results: A 50-year-old healthy female presented with decreased vision in both eyes. A Topcon DRI OCT Triton Plus swept source OCT system was used to visualize and evaluate the retinal and choroidal vascular plexus. Patchy and confluent dark areas in the superficial and deep retinal capillary plexus and choriocapillaris corresponded to areas of hypoperfusion, analyzed as areas of ischemia. Conclusions and Importance: VKH disease is characterized by ocular, neurological, and integumentary findings in its complete form. We present a case of incomplete disease in a 50-year-old female evaluated by means of OCTA which is a novel technique that provides depth-resolved images of the retina and choroidal microvasculature without dye injection that allows better visualization and detailed evaluation of the retinal and choroidal vascular plexus.

  6. Multidetector computed tomography angiography of the renal arteries: normal anatomy and its variations

    Directory of Open Access Journals (Sweden)

    Carlos Fernando de Mello Júnior

    2016-06-01

    Full Text Available Abstract Conventional angiography is still considered the gold standard for the study of the anatomy and of vascular diseases of the abdomen. However, the advent of multidetector computed tomography and techniques of digital image reconstruction has provided an alternative means of performing angiography, without the risks inherent to invasive angiographic examinations. Therefore, within the field of radiology, there is an ever-increasing demand for deeper knowledge of the anatomy of the regional vasculature and its variations. Variations in the renal vascular system are relatively prevalent in the venous and arterial vessels. For various conditions in which surgical planning is crucial to the success of the procedure, knowledge of this topic is important. The aim of this study was to familiarize the general radiologist with variations in the renal vascular system. To that end, we prepared a pictorial essay comprising multidetector computed tomography images obtained in a series of cases. We show patterns representative of the most common anatomical variations in the arterial blood supply to the kidneys, calling attention to the nomenclature, as well as to the clinical and surgical implications of such variations.

  7. Multidetector computed tomography angiography of the renal arteries: normal anatomy and its variations

    Energy Technology Data Exchange (ETDEWEB)

    Mello Junior, Carlos Fernando de; Araujo Neto, Severino Aires; Carvalho Junior, Arlindo Monteiro de; Negromonte, Gustavo Ramalho Pessoa; Oliveira, Carollyne Dantas de [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Reboucas, Rafael Batista, E-mail: severinoaires@hotmail.com [Faculdade de Ciencias Medicas da Paraiba, Joao Pessoa, PB (Brazil)

    2016-05-15

    Conventional angiography is still considered the gold standard for the study of the anatomy and of vascular diseases of the abdomen. However, the advent of multidetector computed tomography and techniques of digital image reconstruction has provided an alternative means of performing angiography, without the risks inherent to invasive angiographic examinations. Therefore, within the field of radiology, there is an ever-increasing demand for deeper knowledge of the anatomy of the regional vasculature and its variations. Variations in the renal vascular system are relatively prevalent in the venous and arterial vessels. For various conditions in which surgical planning is crucial to the success of the procedure, knowledge of this topic is important. The aim of this study was to familiarize the general radiologist with variations in the renal vascular system. To that end, we prepared a pictorial essay comprising multidetector computed tomography images obtained in a series of cases. We show patterns representative of the most common anatomical variations in the arterial blood supply to the kidneys, calling attention to the nomenclature, as well as to the clinical and surgical implications of such variations. (author)

  8. Cardiac Computed Tomography Angiography for Imaging Coronary Arteriovenous Malformation: a Case Report

    Directory of Open Access Journals (Sweden)

    Zsuzsanna Suciu

    2014-02-01

    Full Text Available Background: Coronary arteriovenous malformation is a rare congenital disease consisting mainly in a direct communication between a coronary artery and any one of the four cardiac chambers, coronary sinus, pulmonary arteries or veins. This disease can lead to various cardiovascular events, their severity depending on the degree of the malformation. Case report: We present the case of a 56-year-old male patient, who was admitted to our institution with dyspnea, palpitation and chest pain, having a history of hypertension and hyperlipidemia, and an abnormal electrocardiogram. Physical examination did not reveal any alterations and the cardiac enzymes were in normal ranges. Cardiac computed tomography was performed before any other invasive studies, with a 64-row scanner (Somatom Sensation multislice 64 equipment, Siemens after intravenous administration of non-ionic contrast material. CT scan revealed a large (2-2.5 mm coronary fistula originating from the LAD to the main pulmonary artery, and multiple significant atherosclerotic coronary lesions. Coronary angiography confirmed the arteriovenous malformation between LAD and pulmonary artery, associated with three vascular coronary artery disease. Conclusions: Cardiac computed tomography angiography can help for a non-invasive diagnosis of the coronary artery malformations, in the same time revealing anatomic details which can be particulary useful for choosing the appropriate management strategy (surgical planning, interventional treatment or optimum medical treatment

  9. Could post-mortem computed tomography angiography inform cardiopulmonary resuscitation research?

    Science.gov (United States)

    Rutty, Guy N; Robinson, Claire; Amoroso, Jasmin; Coats, Tim; Morgan, Bruno

    2017-09-23

    Firstly, to develop an optimised chest compression post mortem computed tomography angiography protocol in the adult human during closed chest compression to investigate cardiopulmonary resuscitation blood flow, and secondly to provide preliminary observations of post-mortem anatomical cardiac chamber movement using a novel radiolucent static chest compression device. Variable volumes of radiological contrast agent were injected intravenously into a series of consented human cadavers. Each cadaver had chest compressions delivered with a LUCAS™2 mechanical chest compressor. Following each cycle of chest compressions, each cadaver was imaged with a Toshiba Aquilion CXL 128 slice computed tomography (CT) scanner to investigate the extent of contrast distribution. A chest compression simulator was then designed and built to allow static CT imaging of 1cm incremental cadaver chest compressions to a depth of 5cm. Mechanical compressions: Ten cases were recruited for the CT angiography component of the study. Two were subsequently excluded from the study at the time of the initial, non-contrast PMCT scan. A further case was recruited in Emergency Department (ED). CT demonstrable antegrade arterial contrast distribution was achieved in 2 cases. The other 7 cases, including that undertaken in ED shortly after death, showed venous retrograde flow. Incremental compressions: Five new cases underwent incremental chest compression imaging. All cases demonstrated compression of the sternum, ribs, atria and great vessels. The right and left ventricles were not compressed, but moved laterally and inferiorly, further into the left chest cavity. The left hemi-diaphragm, stomach and liver moved inferiorly. The sternum, ventricles, hemi-diaphragm, stomach and liver all moved back to their original position on incremental release. The study suggests that with further protocol modification and access to human cadavers as near to death as possible, chest compression post mortem computed

  10. Density evaluation by computerized tomography in plain soils over different manipulation systems; Avaliacao da densidade pelo metodo da tomografia computadorizada de um planossolo sob diferentes sistemas de manejo

    Energy Technology Data Exchange (ETDEWEB)

    Pedrotti, Alceu [Lavras Univ., MG (Brazil). Dept. de Ciencia do Solo; Pauletto, Eloy Antonio [Pelotas Univ., RS (Brazil). Dept. de Solos; Crestana, Silvio [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Sao Carlos, SP (Brazil). Centro Nacional de Pesquisa e Desenvolvimento de Instrumentacao Agropecuaria (CNPDIA)

    1996-08-01

    The objective of this paper is the evaluation of a plain soil density in different culture systems determined by X ray computerized tomography.It was observed a larger variation in densities in soils profiles analysed. The identification of layers is better utilising computerized tomography than others technic 1 fig.

  11. [The diagnostic value of computerized tomography in mediastinal diseases depending on their localization].

    Science.gov (United States)

    Sommer, B; Doppman, J L; Stelter, W; Mayr, B; Rienmüller, R; Lissner, J

    1981-04-01

    The diagnostic ranking and importance of computerised tomography was examined in 116 patients with abnormal findings in the mediastinal region, and was compared with conventional, non-invasive x-ray examinations. This method also yielded significant CT-specific additional information in the anterior mediastinum in 74.4% of the cases, in the mesomediastinum in 69.1%, in the posterior mediastinum in 79.2% in the upper thoracic aperture in 94.4% and in the paracardial region in 100% of the cases. The hilar region is an exception; in 68.8% of the cases, both methods were rated equal, whereas in 28.1% of the cases assessment via the CT method was even inferior. The specific additional information furnished by the CT method justifies a wider application of CT in solving the following problems concerning the mediastinum. -- clarification of a suspected but not yet established space-occupying growth in the mediastinum, before using invasive diagnostic methods such as mediastinoscopy and angiography; -- staging of an already identified primary mediastinal tumor of malignant lymphoma; -- in case of suspected changes in the large mediastinal vessels before employing angiography; -- on-target in the following diseases: bronchogenic carcinoma (because of improved pretherapeutic staging according to the TNM system), myasthenia gravis and identification of thymoma, hyperparathyroidism with suspected dystopic parathyroid glands.

  12. The comparative study on diagnostic validity of cerebral aneurysm by computed tomography angiography versus digital subtraction angiography after subarachnoid hemorrhage

    Directory of Open Access Journals (Sweden)

    Masih Saboori

    2011-01-01

    Full Text Available Background: In order to declare the preoperative diagnostic value of brain aneurysms, two radiological modalities, computed tomographic angiography and digital subtraction angiography were compared. Methods: In this descriptive analytic study, diagnostic value of computed tomographic angiography (CTA was com-pared with digital subtraction angiography (DSA. Sensitivity, specificity, positive and negative predictive values were calculated and compared between the two modalities. All data were analyzed with SPSS software, version 16. Results: Mean age of patients was 49.5 ± 9.13 years. 57.9 % of subjects were female. CTA showed 89% sensitivity and 100% specificity whereas DSA demonstrated 74% sensitivity and 100% specificity. Positive predictive value of both methods was 100%, but negative predictive value of CTA and DSA was 85% and 69%, respectively. Conclusions: Based on our data, CTA is a valuable diagnostic modality for detection of brain aneurysm and su-barachnoid hemorrhage.

  13. Comparison of excretory urography, angiography, ultrasound and computed tomography for T category staging of renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Tammela, T.L.J.; Leinonen, A.S.S.; Kontturi, M.J. (Dept. of Surgery and Dept. of Diagnostic Radiology, Oulu Univ. Hospital (Finland))

    1991-01-01

    The diagnostic significance of excretory urography, renal angiography, ultrasound and computed tomography for predicting the stage of tumours was evaluated by comparing their results with preoperative and histopathological findings. Thirty-nine out of 178 patients operated on for renal cell carcinoma from 1981 to 1988 were subjected to all four diagnostic procedures. The T-stage was determined correctly by computed tomography in 80% of the cases, by ultrasound in 74.5%, by renal angiography in 64% and by excretory urography in 56.5%. Excretory urography did not give any significant additional information on the T category compared with the other imaging methods. Angiography is still of value in that it gives preoperative information on the collateral circulation and the number of renal arteries and their location. (au).

  14. Accurately Diagnosing Uric Acid Stones from Conventional Computerized Tomography Imaging: Development and Preliminary Assessment of a Pixel Mapping Software.

    Science.gov (United States)

    Ganesan, Vishnu; De, Shubha; Shkumat, Nicholas; Marchini, Giovanni; Monga, Manoj

    2018-02-01

    Preoperative determination of uric acid stones from computerized tomography imaging would be of tremendous clinical use. We sought to design a software algorithm that could apply data from noncontrast computerized tomography to predict the presence of uric acid stones. Patients with pure uric acid and calcium oxalate stones were identified from our stone registry. Only stones greater than 4 mm which were clearly traceable from initial computerized tomography to final composition were included in analysis. A semiautomated computer algorithm was used to process image data. Average and maximum HU, eccentricity (deviation from a circle) and kurtosis (peakedness vs flatness) were automatically generated. These parameters were examined in several mathematical models to predict the presence of uric acid stones. A total of 100 patients, of whom 52 had calcium oxalate and 48 had uric acid stones, were included in the final analysis. Uric acid stones were significantly larger (12.2 vs 9.0 mm, p = 0.03) but calcium oxalate stones had higher mean attenuation (457 vs 315 HU, p = 0.001) and maximum attenuation (918 vs 553 HU, p uric acid stones. A combination of stone size, attenuation intensity and attenuation pattern from conventional computerized tomography can distinguish uric acid stones from calcium oxalate stones with high sensitivity and specificity. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  15. Cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial region: a systematic review of the literature.

    NARCIS (Netherlands)

    Vos, W. De; Casselman, J.W.; Swennen, G.R.

    2009-01-01

    This study reviewed the literature on cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial (OMF) region. A PUBMED search (National Library of Medicine, NCBI; revised 1 December 2007) from 1998 to December 2007 was conducted. This search revealed 375 papers, which were

  16. 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 t...

  17. Identification of discrete vascular lesions in the extremities using post-mortem computed tomography angiography – Case reports

    NARCIS (Netherlands)

    Haakma, Wieke|info:eu-repo/dai/nl/413649946; Rohde, Marianne; Uhrenholt, Lars; Pedersen, Michael; Boel, Lene Warner Thorup

    2017-01-01

    In this case report, we introduced post-mortem computed tomography angiography (PMCTA) in three cases suffering from vascular lesions in the upper extremities. In each subject, the third part of the axillary arteries and veins were used to catheterize the arms. The vessels were filled with a barium

  18. Automatic detection of aorto-femoral vessel trajectory from whole-body computed tomography angiography data sets

    NARCIS (Netherlands)

    X. Gao (Xinpei); P.H. Kitslaar (Pieter); R.P.J. Budde (Ricardo P.J.); S. Tu (Shengxian); M.A. de Graaf (Michiel); L. Xu (Liang); B. Xu (Bo); A. Scholte; J. Dijkstra (Jouke); J.H.C. Reiber (Johan H. C.)

    2016-01-01

    textabstractExtraction of the aorto-femoral vessel trajectory is important to utilize computed tomography angiography (CTA) in an integrated workflow of the image-guided work-up prior to trans-catheter aortic valve replacement (TAVR). The aim of this study was to develop a new, fully-automated

  19. Post-mortem computed tomography angiography utilizing barium sulfate to identify microvascular structures : a preliminary phantom model and case study

    NARCIS (Netherlands)

    Haakma, Wieke; Rohde, Marianne; Kuster, Lidy; Uhrenholt, Lars; Pedersen, Michael; Boel, Lene Warner Thorup

    2016-01-01

    We investigated the use of computer tomography angiography (CTA) to visualize microvascular structures in a vessel-mimicking phantom and post-mortem (PM) bodies. A contrast agent was used based on 22% barium sulfate, 20% polyethylene glycol and 58% distilled water. A vessel-mimicking phantom

  20. Computerized Tomography Technique for the Investigation of the Maxillary First Molar Mesiobuccal Root

    Directory of Open Access Journals (Sweden)

    Stefano Corbella

    2013-01-01

    Full Text Available The aim of this paper was to review the literature about the use of computerized tomography to evaluate the presence and characteristics of the second mesiobuccal canal in the maxillary first molar. An electronic search was performed. Frequencies of the presence of second mesiobuccal canal and root anatomy characteristics were extracted from the selected studies. Pooled frequencies were calculated as weighted means. Seven articles were included. A second mesiobuccal canal was present in 59.32% of the teeth, and it was noncommunicating in 58.45% of teeth presenting the canal itself. The most common root canal morphology was single canal or two separated canals. The present paper showed that cone beam CT is a viable radiologic device for the evaluation of the mesiobuccal root of maxillary first molars. In fact, it was observed that the frequency of second mesiobuccal canal detection is similar to those presented by clinical studies or micro-CT evaluations.

  1. The influence of species composition on flow field's optical computerized tomography diagnosis

    Science.gov (United States)

    Yun-yun, Chen; Fang, Gu; Ling-bing, Bu; Ying-ying, Zhang

    2017-07-01

    The species composition is one of the factors which could affect the refractive index of flow fields. So, the determination of species composition should be a key point, when optical computerized tomography (OCT) methods are applied to measure the key parameters of flow fields. In this paper, the influence of species composition on flow field's temperature diagnosis will be discussed both in theory and experiment. The final results manifest that the determination of species composition could affect not only the specific temperature values, but also the structure and distribution of the temperature. Meanwhile, it is also found that the nonlinear regular of the maximal temperature variation with the distance between the cross section and nozzle is the same in different models. Finally, the condition, which could be applied to judge whether the effect of species composition can be omitted, is proposed.

  2. Computerized tomography, stereolithography and dental implants in the rehabilitation of oral cancer patients.

    Science.gov (United States)

    Patel, Mital; Al-Momani, Zaid; Hodson, Nicholas; Nixon, Peter; Mitchell, David

    2013-09-01

    As survival rates improve it is important to consider the quality of life for oral cancer patients post-treatment. The primary goal is removal of the tumour, however, with a gradual increase in survival rates, post-operative rehabilitation is now becoming increasingly important. Specialists in restorative dentistry, along with oral and maxillofacial surgeons, general dental practitioners and other members of the multidisciplinary team play a vital role in planning treatment for, and rehabilitating, these patients. This paper presents a case series to show how recent advances in computerized tomography (CT) and the use of stereolithographic models can help in the rehabilitation of oral cancer patients. The principles discussed can also be applied to other patients undergoing dental implant treatment to help plan and carry out treatment and improve the quality of peri-implant tissues.

  3. A water-soluble triiodo amino acid and its dendrimer conjugate for computerized tomography (CT imaging

    Directory of Open Access Journals (Sweden)

    MARTIN W. BRECHBIEL

    2005-02-01

    Full Text Available Prolonging the circulation of an imaging agent is vital for making it suitable for blood pool (vascular imaging. Medical applications of vascular imaging include cardiovascular disease, abnormal capillary permeability, and tumor neovascularity. As low molecular weight computerized tomography (CT enhancement agents are characterized by inconveniently fast clearance, macromolecular compounds (both natural and synthetic have gained a wide recongnition for possessing better characteristics for performing blood imaging tasks. Herein, the syntheses and characterization of a new water-soluble triiodo amino acid, 3-[(N,N-dimethylaminoacetyl amino]-a-ethyl-2,4,6-triiodobenzenepropanoic acid (DMAA-IPA and its Starburst PAMAMgeneration 4.0 dendrimer conjugate, G-4-(DMAA-IPA37 are described. The applicability of G-4-(DMAA-IPA37 as a potential macromolecular angiographic CT contrast agent is discussed. The linear relationship between organically bound iodine concentration and CT Hounsfield units has been established thus allowing for quantification uses of CT imaging as well.

  4. Dose evaluation in diagnostic for computerized tomography; Evaluacion de dosis en diagnostico por tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Flores, W.; Borges, J.C.; Mota, H. [Universidad Federal de Rio de Janeiro, PEN/COPPE/UFRJ. Caixa Postal 68509. 21945-970 Rio de Janeiro (Brazil)

    1998-12-31

    The patients which are subjected to computerized tomography tests are exposed to relatively high doses given as result doses on organs that are not matter to test. It was realized a dose levels raising in patients subjected to tests by T C, utilizing to measure this magnitude, TLD-100 thermoluminescent dosemeters which were put directly on the patient, in eye regions, thyroid, breast and navel; founding doses fluctuating between 29.10-49.39 mGy in organs examined and dose values between 0.21-29.10 mGy for organs that no matter to test. The applications of ionizing radiations in medicine do not have dose limits, but paying attention to the radiological protection optimization principle, it is recommended the use of clothes to anti-rays protection for zones not examined, getting with this to reduce the level doses as low as possible, without this to diminish the test quality. (Author)

  5. Planosol soil sample size for computerized tomography measurement of physical parameters

    Directory of Open Access Journals (Sweden)

    Pedrotti Alceu

    2003-01-01

    Full Text Available Computerized tomography (CT is an important tool in Soil Science for noninvasive measurement of density and water content of soil samples. This work aims to describe the aspects of sample size adequacy for Planosol (Albaqualf and to evaluate procedures for statistical analysis, using a CT scanner with a 241Am source. Density errors attributed to the equipment are 0.051 and 0.046 Mg m-3 for horizons A and B, respectively. The theoretical value for sample thickness for the Planosol, using this equipment, is 4.0 cm for the horizons A and B. The ideal thickness of samples is approximately 6.0 cm, being smaller for samples of the horizon B in relation to A. Alternatives for the improvement of the efficiency analysis and the reliability of the results obtained by CT are also discussed, and indicate good precision and adaptability of the application of this technology in Planosol (Albaqualf studies.

  6. A motion artefact study and locally deforming objects in computerized tomography

    Science.gov (United States)

    Hahn, Bernadette N.

    2017-11-01

    Movements of the object during the data collection in computerized tomography can introduce motion artefacts in the reconstructed image. They can be reduced by employing information about the dynamic behaviour within the reconstruction step. However, inaccuracies concerning the movement are inevitable in practice. In this article, we give an explicit characterization of what is visible in an image obtained by a reconstruction algorithm with incorrect motion information. Then, we use this result to study in detail the situation of locally deforming objects, i.e. individual parts of the object have a different dynamic behaviour. In this context, we prove that additional artefacts arise due to the global nature of the Radon transform, even if the motion is exactly known. Based on our analysis, we propose a numerical scheme to reduce these artefacts in the reconstructed image. All our results are illustrated by numerical examples.

  7. Computed Tomography Angiography is the Definitive Vascular Imaging Modality for Penetrating Neck Injury: A South African Experience.

    Science.gov (United States)

    Madsen, A S; Kong, V Y; Oosthuizen, G V; Bruce, J L; Laing, G L; Clarke, D L

    2017-09-01

    Computed tomography angiography has become central to the diagnostic algorithm for penetrating neck injury, but despite its widespread use the literature to support this adoption is limited. We reviewed our experience with computed tomography angiography for the identification of vascular trauma in hemodynamically stable patients with penetrating neck injury at a major trauma center in South Africa. A prospectively kept trauma registry capturing data in real time was retrospectively reviewed. All patients with penetrating neck injury investigated with computed tomography angiography as the initial vascular investigation during a 47-month period were included. A total of 380 patients were included. Indications for computed tomography angiography were as follows: hard signs (13), soft signs (201), no signs but proximity/zone I or III wounds (141), and undefined signs of vascular injury (25). Of the 380 scans, 7 (1.8%) were indeterminate, 299 (78.7%) negative, and 74 (19.5%) positive for a vascular injury (54 arterial and 20 isolated venous injury). Eight were false positive and 4 false negative. The sensitivity, specificity, positive, and negative predictive values for detecting arterial injury were 93.9%, 97.5%, 85.2%, and 99.1%, respectively. Overall, the yield for demonstrating "true arterial injury" was 12.1% (46/380); hard signs: 76.9% (10/13), soft signs: 16.4% (33/201), and no signs: 2.1% (3/141) which all were secondary to gunshot wounds). Only 8.4% (32/380) required intervention for arterial injury and none for isolated venous injury (hard signs: 62.0%, soft signs: 11.4%, and no signs: 0.7%). No serious complications resulted from computed tomography angiography. Computed tomography angiography is a safe and effective imaging modality for the investigation of vascular trauma post penetrating neck injury. Asymptomatic patients with stab wounds do not need to be imaged regardless of proximity concerns. Symptomatic stable patients including a subgroup with hard

  8. Assessing Deep Retinal Capillary Ischemia in Paracentral Acute Middle Maculopathy by Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Nemiroff, Julia; Kuehlewein, Laura; Rahimy, Ehsan; Tsui, Irena; Doshi, Rishi; Gaudric, Alain; Gorin, Michael B; Sadda, SriniVas; Sarraf, David

    2016-02-01

    To assess microvascular blood flow of the deep retinal capillary plexus in eyes with paracentral acute middle maculopathy using optical coherence tomography (OCT) angiography. Retrospective, multicenter observational case series. Clinical and multimodal imaging findings from 8 patients with paracentral acute middle maculopathy were reviewed and analyzed. OCT angiography scans were analyzed and processed, and vessel density was calculated. Eight patients (7 male, 1 female, aged 9-82 years) were included. OCT angiography was obtained at either the acute (4 cases) or old stage (4 cases). Scans of the deep capillary plexus showed preservation of perfusion in acute lesions and capillary attenuation in old cases. Cases of central retinal artery occlusion showed marked loss of the deep capillary plexus. The mean vessel density of the superficial capillary plexus in normal fellow eyes was 12.8 ± 1.8 mm(-1) vs 12.1 ± 1.9 mm(-1) in eyes with paracentral acute middle maculopathy (reduction -6.0%, P = .08). The mean vessel density of the deep capillary plexus in normal fellow eyes was 17.5 ± 1.4 mm(-1) vs 14.7 ± 3.5 mm(-1) in eyes with paracentral acute middle maculopathy (reduction -19.4%, P = .04). This significant difference was representative of the eyes with old lesions. Paracentral acute middle maculopathy lesions correspond to preservation of perfusion in focal acute lesions and to pruning of the plexus in old cases. Cases of central retinal artery occlusion demonstrate marked hypoperfusion of the deep capillary plexus. Our study further supports an ischemic pathogenesis of this retinal vasculopathy. Published by Elsevier Inc.

  9. [Flow density measurements using optical coherence tomography angiography : Impact of age and gender].

    Science.gov (United States)

    Alnawaiseh, M; Brand, C; Lauermann, J L; Eter, N

    2017-07-19

    This article presents the normative data for flow density measured using optical coherence tomography (OCT) angiography and the impact of age and gender is evaluated. In this study 58 eyes from 58 healthy volunteers with no history of any ocular disease or ocular surgery were included. The OCT angiography imaging was performed using the RTVue XR Avanti with the AngioVue (Optovue, Fremont, CA). The macula was imaged using a 3 × 3 mm scan, and the flow density data in the superficial retinal OCT angiogram and deep retinal OCT angiogram were extracted and analyzed. The groups were compared using the Mann-Whitney U‑test and the degree of correlation between two variables was expressed as the Spearman's correlation coefficient (rSp.) RESULTS: The mean subject age was 38.3 ± 14.6 years. The flow density (whole en face) in the deep retinal OCT angiogram was significantly higher compared to the flow density in the superficial retinal OCT angiogram (p density in superficial and deep OCT angiograms of the macula between males (n = 27) and females (n = 31). There was a significant correlation between the flow density in the deep retinal OCT angiogram and age (rSp. = -0.41, p = 0.001). Whereas gender has no impact on the flow density measured using OCT angiography, there was a significant correlation between the flow density in the deep retinal OCT angiogram and age.

  10. 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.

  11. Renal calyceal anatomy characterization with 3-dimensional in vivo computerized tomography imaging.

    Science.gov (United States)

    Miller, Joe; Durack, Jeremy C; Sorensen, Mathew D; Wang, James H; Stoller, Marshall L

    2013-02-01

    Calyceal selection for percutaneous renal access is critical for safe, effective performance of percutaneous nephrolithotomy. Available anatomical evidence is contradictory and incomplete. We present detailed renal calyceal anatomy obtained from in vivo 3-dimentional computerized tomography renderings. A total of 60 computerized tomography urograms were randomly selected. The renal collecting system was isolated and 3-dimensional renderings were constructed. The primary plane of each calyceal group of 100 kidneys was determined. A coronal maximum intensity projection was used for simulated percutaneous access. The most inferior calyx was designated calyx 1. Moving superiorly, the subsequent calyces were designated calyx 2 and, when present, calyx 3. The surface rendering was rotated to assess the primary plane of the calyceal group and the orientation of the select calyx. The primary plane of the upper pole calyceal group was mediolateral in 95% of kidneys and the primary plane of the lower pole calyceal group was anteroposterior in 95%. Calyx 2 was chosen in 90 of 97 simulations and it was appropriate in 92%. Calyx 3 was chosen in 7 simulations but it was appropriate in only 57%. Calyx 1 was not selected in any simulation and it was anteriorly oriented in 75% of kidneys. Appropriate lower pole calyceal access can be reliably accomplished with an understanding of the anatomical relationship between individual calyceal orientation and the primary plane of the calyceal group. Calyx 2 is most often appropriate for accessing the anteroposterior primary plane of the lower pole. Calyx 1 is most commonly oriented anterior. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. Sublingual nitroglycerin administration in coronary computed tomography angiography: a systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Takx, Richard A.P. [Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Sucha, Dominika; Leiner, Tim [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Park, Jakob [Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); University of Heidelberg, Department of Cardiology, Heidelberg (Germany); Hoffmann, Udo [Harvard Medical School, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States)

    2015-12-15

    To systematically investigate the literature for the influence of sublingual nitroglycerin administration on coronary diameter, the number of evaluable segments, image quality, heart rate and blood pressure, and diagnostic accuracy of coronary computed tomography (CT) angiography. A systematic search was performed in PubMed, EMBASE and Web of Science. The studies were evaluated for the effect of sublingual nitroglycerin on coronary artery diameter, evaluable segments, objective and subjective image quality, systemic physiological effects and diagnostic accuracy. Due to the heterogeneous reporting of outcome measures, a narrative synthesis was applied. Of the 217 studies identified, nine met the inclusion criteria: seven reported on the effect of nitroglycerin on coronary artery diameter, six on evaluable segments, four on image quality, five on systemic physiological effects and two on diagnostic accuracy. Sublingual nitroglycerin administration resulted in an improved evaluation of more coronary segments, in particular, in smaller coronary branches, better image quality and improved diagnostic accuracy. Side effects were mild and were alleviated without medical intervention. Sublingual nitroglycerin improves the coronary diameter, the number of assessable segments, image quality and diagnostic accuracy of coronary CT angiography without major side effects or systemic physiological changes. (orig.)

  13. A STUDY TO COMPARE FUNDUS FLUORESCEIN ANGIOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY IN AGE RELATED MACULAR DEGENERATION

    Directory of Open Access Journals (Sweden)

    Rani Sujatha

    2016-02-01

    Full Text Available PURPOSE To compare the diagnostic accuracy of optical coherence tomography with Fundus Fluorescein Angiography in diagnosing Age related macular degeneration. METHODS A total 25 patients newly diagnosed as Age related macular degeneration were included in the study. The study was done during the time period between August 2013 to November 2015 this is a prospective randomized hospital based study. RESULTS Maximum no of patients affected belonged to the age group of 50-70 years and 60% were females. The most common symptom was defective vision accounting for 92%. Hypertension and hyperlipidemia were the most common risk factors. 12% of the cases had unilateral disease and 88% had bilateral disease. 6% of eyes were normal in both FFA and OCT. 62% of the eyes by FFA and 61% of the eyes by OCT had dry ARMD and 32 % of the eye by FFA and 33 % by OCT had wet ARMD. CONCLUSION Fundus Fluorescein Angiography is the gold standard tool for screening ARMD and OCT is more specific in detecting early subretinal neovascular membrane and also to assess the activity of the neovascular membranes. Hence OCT is superior to FFA in diagnosing early wet ARMD and thus helps in early management of patients with ARMD.

  14. Coronary stent occlusion: reverse attenuation gradient sign observed at computed tomography angiography improves diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Minghua; Zhang, Jiayin [Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Department of Radiology, Shanghai (China); Zhang, Qingyong; Pan, Jingwei; Lu, Zhigang; Wei, Meng [Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Department of Cardiology, Shanghai (China)

    2014-09-26

    To evaluate the incidence and diagnostic performance of reverse attenuation gradient (RAG) sign in patients with coronary stent occlusion. We retrospectively included patients with suspected restenosis who underwent both coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) within 2 weeks. Stent occlusion at CCTA was defined as (1) complete contrast filling defect of large calibre stents (at least 3 mm), or (2) presence of RAG sign in patients with small calibre stents (less than 3 mm) or (3) presence of RAG sign in patients with non-diagnostic image quality of stents. The diagnostic performance of RAG sign was further assessed by comparison to ICA results. A total of 162 patients with 231 implanted stents were included. ICA confirmed stent occlusion in 59 patients (99 stents). RAG sign was present in 59.3 % (35/59) of all stent occlusions. As shown by patient-based analysis, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of our diagnostic criteria for detection of stent occlusion were 79.7 % (47/59), 100 % (103/103), 100 % (47/47) and 89.6 % (103/115) respectively. Superior diagnostic performance was confirmed by receiver operating characteristic (ROC) analysis with an area under the curve of 0.898. RAG sign observed at CCTA in patients with coronary stenting represents reverse collateral flow distal to stents and is highly specific to indicate stent occlusion. (orig.)

  15. Diagnostic performance of fusion of myocardial perfusion imaging (MPI) and computed tomography coronary angiography

    Science.gov (United States)

    Santana, Cesar A.; Garcia, Ernest V.; Faber, Tracy L.; Sirineni, Gopi K. R.; Esteves, Fabio P.; Sanyal, Rupan; Halkar, Raghuveer; Ornelas, Mario; Verdes, Liudmila; Lerakis, Stamatios; Ramos, Julie J.; Aguadé-Bruix, Santiago; Cuéllar, Hugo; Candell-Riera, Jaume; Raggi, Paolo

    2011-01-01

    Background We evaluated the incremental diagnostic value of fusion images of coronary computed tomography angiography (CTA) and myocardial perfusion imaging (MPI) over MPI alone or MPI and CTA side-by-side to identify obstructive coronary artery disease (CAD > 50% stenosis) using invasive coronary angiography (ICA) as the gold standard. Methods 50 subjects (36 men; 56 ± 11 years old) underwent rest-stress MPI and CTA within 12-26 days of each other. CTAs were performed with multi-detector CT-scanners (31 on 64-slice; and 19 on 16-slice). 37 patients underwent ICA while 13 subjects did not because of low (area under the curve (AUC) for fused images: 0.89; P = .005 vs MPI, P = .04 vs side-by-side MPI-CTA) and for localization of CAD to the left anterior descending coronary artery (AUC: 0.82, P < .001 vs MPI; P = .007 vs side-by-side MPI-CTA). There was a non-significant trend for better detection of multi-vessel disease with fusion. Conclusions Using ICA as the gold standard, fusion imaging provided incremental diagnostic information compared to MPI alone or side-by-side MPI-CTA for the diagnosis of obstructive CAD and for localization of CAD to the left anterior descending coronary artery. PMID:19156478

  16. Choroidal neovascularisation on optical coherence tomography angiography in punctate inner choroidopathy and multifocal choroiditis.

    Science.gov (United States)

    Levison, Ashleigh L; Baynes, Kimberly M; Lowder, Careen Y; Kaiser, Peter K; Srivastava, Sunil K

    2017-05-01

    To describe the findings seen on optical coherence tomography angiography (OCTA) in patients with punctate inner choroidopathy (PIC) and multifocal choroiditis and panuveitis (MCP) complicated by choroidal neovascular membranes. This was an Institutional Review Board-approved prospective, descriptive case series. 12 patients with PIC and MCP complicated by choroidal neovascularisation (CNV) were included. Each patient underwent slit-lamp examination by a uveitis specialist followed by conventional spectral domain OCT imaging of the macula. OCTA images of the macula were then obtained. 12 patients were enrolled in the study, out of which 9 patients were followed longitudinally. CNV was identified in 11 of the 12 patients. In all patients where fluorescein angiography (FA) was inconclusive for presence of CNV, OCTA identified CNV. Various lesions on OCT suggestive of activity correlated with changes in the vascular structure of OCTA to confirm suspicion of clinical activity. In patients with PIC and MCP complicated by CNV, OCTA successfully identified underlying CNV. Given the difficulty of differentiating inflammatory lesions from early CNV on OCT and FA, OCTA may provide a valuable method of monitoring patients with posterior uveitis highly correlated with development of CNV. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Intravenous flat-detector computed tomography angiography for symptomatic cerebral vasospasm following aneurysmal subarachnoid hemorrhage.

    Science.gov (United States)

    Jeon, Jin Pyeong; Sheen, Seung Hun; Cho, Yong-Jun

    2014-01-01

    The study evaluated the diagnostic accuracy of intravenous flat-detector computed tomography (IV FDCT) angiography in assessing hemodynamically significant cerebral vasospasm in patients with subarachnoid hemorrhage (SAH) with digital subtraction angiography (DSA) as the reference. DSA and IV FDCT were conducted concurrently in patients suspected of having symptomatic cerebral vasospasm postoperatively. The presence and severity of vasospasm were estimated according to location (proximal versus distal). Vasospasm >50% was defined as having hemodynamic significance. Vasospasms FDCT showed a sensitivity of 95.7%, specificity of 92.3%, positive predictive value of 93.6%, and negative predictive value of 94.7% for detecting vasospasm (>50%) with DSA as the reference. Bland-Altman plots revealed good agreement of assessing vasospasm between the two tests. The discrepancy of vasospasm severity was more noted in the distal location with high-severity. However, it was not statistically significant (Spearman's rank test; r = 0.15, P = 0.35). Therefore, IV FDCT could be a feasible noninvasive test to evaluate suspected significant vasospasm in SAH.

  18. Optical Coherence Tomography Angiography in Children with Leber-Coats Disease.

    Science.gov (United States)

    Fortunato, Michele; Turtoro, Angela; Cennamo, Gilda

    2017-01-01

    The aim of this work was to describe the optical coherence tomography (OCT) angiography (OCTA) features in paediatric Leber-Coats disease. Three children presenting with unilateral, clinically active Leber-Coats disease were evaluated using spectral domain OCT and OCTA. OCT angiograms were analysed and compared with the current literature. All 3 OCT angiograms showed that the vessels had lost most of their collateral branches and presented many loops. The capillaries were rarefied and anomalies in vessel size, vasodilatation, and macroaneurysms were evident. This is the first case series of OCTA performed in children with Leber-Coats disease. OCTA is a non-invasive and non-contact technique, which can be considered of fundamental importance for the diagnosis, clinical management, and follow-up of the disease. © 2017 S. Karger AG, Basel.

  19. Safety criteria for contrast administration in computed tomography cardiac angiography: perception of nursing

    Directory of Open Access Journals (Sweden)

    Laura Vargas Acauan

    2015-09-01

    Full Text Available Objective: to understand the perception of the nursing team about the safety criteria adopted in the use and administration of iodinated contrast media on computed tomography cardiac angiography. Methods: a descriptive study with a qualitative approach. The data were produced using the semi-structured interview with twelve participants from two diagnostic imaging centers. Results: two thematic categories emerged from the analysis: safe practices in the use and administration of iodinated contrast media and use of light technologies for safe care in the use of iodinated contrast media. Conclusion: it was surmised that safety criteria linked by light and hard technologies are used, but not standardized. To promote effective and quality care focused on patient safety, protocols and guidelines should be established to overcome possible barriers unsafe.

  20. Prognostic assessment of stable coronary artery disease as determined by coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Nielsen, Lene H; Bøtker, Hans Erik; Sørensen, Henrik T

    2016-01-01

    Aims: To examine the 3.5 year prognosis of stable coronary artery disease (CAD) as assessed by coronary computed tomography angiography (CCTA) in real-world clinical practice, overall and within subgroups of patients according to age, sex, and comorbidity. Methods and results: This cohort study......, and comorbidity. Conclusion: Coronary artery disease determined by CCTA in real-world practice predicts the 3.5 year composite risk of late revascularization, myocardial infarction, and all-cause death across different groups of age, sex, or comorbidity burden....... included 16,949 patients (median age 57 years; 57% women) with new-onset symptoms suggestive of CAD, who underwent CCTA between January 2008 and December 2012. The endpoint was a composite of late coronary revascularization procedure >90 days after CCTA, myocardial infarction, and all-cause death...

  1. Non-obstructive coronary artery disease assessed by coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Nielsen, L.; Bøtker, H. E.; Sorensen, H.

    2015-01-01

    Introduction: Coronary CT angiography (CTA) detects non-obstructive coronary artery disease (CAD) that may not be recognized by functional testing, but the prognostic impact is not well understood. This study aimed to compare the risk of myocardial infarction (MI) and all-cause mortality...... in patients without or with non-obstructive and obstructive CAD assessed by coronary CTA. Methods: Consecutive patients without known coronary artery disease (CAD) and with chest pain who underwent coronary CTA (>64-detector row) between January 2007 and December 2012 in the 10 centers participating...... in the Western Denmark Cardiac Computed Tomography Registry were included. The endpoints were 3-year MI or all-cause mortality. The coronary CTA result was defined as normal (0% luminal stenosis), non-obstructive CAD (1%-49% luminal stenosis) or obstructive CAD (>50% luminal stenosis; 1-vessel, 2-vessel, or 3...

  2. Optical Coherence Tomography Angiography Study of Choroidal Neovascularization Associated With Focal Choroidal Excavation.

    Science.gov (United States)

    Chawla, Rohan; Mittal, Kanhaiya; Vohra, Rajpal

    2016-10-01

    The authors report the use of optical coherence tomography angiography (OCTA) (DRI OCT Triton; Topcon, Tokyo, Japan) to localize, characterize, and confirm the presence of a choroidal neovascular membrane in a patient of focal choroidal excavation (FCE) with recent-onset metamorphopsia and visual blurring. En face OCTA images just above the level of the retinal pigment epithelium-Bruch's membrane complex typically showed the presence of a glomerulus-like neovascular network with an adjacent dark area suggestive of a Type 2 choroidal neovascularization (CNV). OCTA was found to be a very useful, noninvasive, and quick imaging modality to detect secondary CNV formation in a case of FCE. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:969-971.]. Copyright 2016, SLACK Incorporated.

  3. Quantitative assessment of the retinal microvasculature using optical coherence tomography angiography

    Science.gov (United States)

    Chu, Zhongdi; Lin, Jason; Gao, Chen; Xin, Chen; Zhang, Qinqin; Chen, Chieh-Li; Roisman, Luis; Gregori, Giovanni; Rosenfeld, Philip J.; Wang, Ruikang K.

    2016-06-01

    Optical coherence tomography angiography (OCTA) is clinically useful for the qualitative assessment of the macular microvasculature. However, there is a need for comprehensive quantitative tools to help objectively analyze the OCT angiograms. Few studies have reported the use of a single quantitative index to describe vessel density in OCT angiograms. In this study, we introduce a five-index quantitative analysis of OCT angiograms in an attempt to detect and assess vascular abnormalities from multiple perspectives. The indices include vessel area density, vessel skeleton density, vessel diameter index, vessel perimeter index, and vessel complexity index. We show the usefulness of the proposed indices with five illustrative cases. Repeatability is tested on both a healthy case and a stable diseased case, giving interclass coefficients smaller than 0.031. The results demonstrate that our proposed quantitative analysis may be useful as a complement to conventional OCTA for the diagnosis of disease and monitoring of treatment.

  4. Diagnostic accuracy of hepatic hemangioma and its decision tree on ultrasonography, computed tomography and angiography

    Energy Technology Data Exchange (ETDEWEB)

    Uesaka, Katsuhiko; Takayasu, Kenichi; Muramatu, Yukio; Moriyama, Noriyuki; Matsue, Hiroto; Yamada, Tatsuya; Hasegawa, Hiroshi

    1988-08-01

    Fifty seven lesions in 31 patients with hepatic hemangioma were concurrently imaged with ultrasonography (US), computed tomography (CT), and angiography (AG). Rates of lesion detection and qualitative diagnosis were 73.7 % and 59.5 %, respectively, for US; 89.5 % and 88.2 % for CT ; ad 89.5 % and 90.2 % for AG. Each of the three imaging methods had a diagnostic rate of 100 % for tumors more than 5 cm. In diagnosing tumors 5 cm or less, US was less sensitive than CT and AG (62.5 % vs 85.0 %). The qualitative diagnostic rate of both CT and AG was 90 % regardless of tumor diameter. As for US, it was 76.5 % in lesions more than 5 cm, and 48.0 % in lesions 5 cm or less. The necessity of decision tree of CT and the other imaging methods in hepatic hemangioma is presented. (Namekawa, K.).

  5. Coronary computed tomography angiography for the evaluation of patients with acute chest pain.

    Science.gov (United States)

    Rajani, R; Brum, R L; Preston, R; Carr-White, G; Berman, D S

    2011-12-01

    Acute chest pain is a common presenting complaint of patients attending emergency room departments. Despite this, it can often be challenging to completely exclude a diagnosis of acute coronary syndrome following an initial standard clinical and biochemical evaluation. As a result of this, patients are often admitted to hospital until the treating clinician is satisfied that this diagnosis can be excluded. This process imparts a significant health economic burden by not only increasing hospital bed occupancy rates but also by the unnecessary layering of diagnostic investigations. With the rapid advances in coronary computed tomography angiography (CTA), there has been considerable interest in whether coronary CTA may be a viable alternative to this current standard care. We review the current literature and supporting evidence for utilising coronary CTA in the evaluation of patients presenting with acute chest pain in terms of its diagnostic accuracy, safety, cost-effectiveness and prognostic implications. © 2011 Blackwell Publishing Ltd.

  6. Corrected coronary opacification decrease from coronary computed tomography angiography: Validation with quantitative 13N-ammonia positron emission tomography.

    Science.gov (United States)

    Benz, Dominik C; Gräni, Christoph; Ferro, Paola; Neumeier, Luis; Messerli, Michael; Possner, Mathias; Clerc, Olivier F; Gebhard, Catherine; Gaemperli, Oliver; Pazhenkottil, Aju P; Kaufmann, Philipp A; Buechel, Ronny R

    2017-07-06

    To assess the functional relevance of a coronary artery stenosis, corrected coronary opacification (CCO) decrease derived from coronary computed tomography angiography (CCTA) has been proposed. The present study aims at validating CCO decrease with quantitative 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging (MPI). This retrospective study consists of 39 patients who underwent hybrid CCTA/PET-MPI. From CCTA, attenuation in the coronary lumen was measured before and after a stenosis and corrected to the aorta to calculate CCO and its decrease. Relative flow reserve (RFR) was calculated by dividing the stress myocardial blood flow (MBF) of a vessel territory subtended by a stenotic coronary by the stress MBF of the reference territories without stenoses. RFR was abnormal in 11 vessel territories (27%). CCO decrease yielded a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for prediction of an abnormal RFR of 73%, 70%, 88%, 47%, and 70%, respectively. CCTA-derived CCO decrease has moderate diagnostic accuracy to predict an abnormal RFR in PET-MPI. However, its high negative predictive value to rule out functional relevance of a given lesion may confer clinical implications in the diagnostic work-up of patients with a coronary stenosis.

  7. Circle of Willis Collateral During Temporary Internal Carotid Artery Occlusion II: Observations From Computed Tomography Angiography.

    Science.gov (United States)

    Wang, Bill Hao; Leung, Andrew; Lownie, Stephen P

    2016-07-01

    The Circle of Willis (CoW) is the most effective collateral circulation to the brain during internal carotid artery (ICA) occlusion. Carotid stump pressure (CSP) is an established surrogate measure of the cerebral collateral circulation. This study aims to use hemodynamic and computed tomography angiography measurements to determine the strongest influences upon the dependent variable, CSP. These findings could help clinicians noninvasively assess the adequacy of the collateral circulation and facilitate surgical risk assessment in an outpatient setting. CSP and mean arterial pressure were measured during carotid endarterectomy or during carotid balloon test occlusion in 92 patients. Intracranial arterial diameters were measured on computed tomography angiography at 16 different locations. Univariate and multivariate analyses were used to determine the key factors associated with CSP. In a subgroup of individuals (n=27) with severe (>70% North American Symptomatic Carotid Endarterectomy Trial) contralateral stenosis or occlusion, the same analysis was performed. The contralateral anterior cerebral artery proximal to anterior communicating artery (A1) of the CoW had the strongest influence upon CSP, followed by the mean arterial pressure, the contralateral ICA diameter, and the anterior communicating artery diameter (R 2=0.364). In the subgroup with high-grade contralateral ICA stenosis, the ipsilateral posterior communicating artery exerted the strongest influence (R 2=0.620). During ICA occlusion, the anterior CoW dominates in preserving collateral flow, especially the contralateral A1 segment. In individuals with high-grade contralateral carotid stenosis, the posterior communicating artery calibre becomes a dominant influence. The most favourable anatomy consists of large contralateral A1 and anterior communicating arteries, and no contralateral carotid stenosis.

  8. Effects of Hyperthyroidism on Coronary Artery Disease: A Computed Tomography Angiography Study.

    Science.gov (United States)

    Beyer, Christoph; Plank, Fabian; Friedrich, Guy; Wildauer, Matthias; Feuchtner, Gudrun

    2017-10-01

    Changes in thyroid hormone concentration can negatively affect the cardiovascular system. Subclinical hyperthyroidism has been linked to an increase of cardiovascular heart disease, however, clinical effects and significance are still uncertain. Therefore, we analyzed coronary computed tomography angiographies of patients with overt and subclinical hyperthyroidism for quantitative parameters and plaque morphology. Seven hundred forty-four (47.1% female) patients who underwent coronary computed tomography angiography were stratified into 3 groups: 51 patients with overt, 74 patients with subclinical hyperthyroidism, and 619 patients with euthyroidism. Analysis included grades of stenosis (no stenosis = 0, mild 70%) and plaque types (noncalcified, mixed, and calcified), segment involvement score (SIS), noncalcified SIS, and high-risk plaque features (napkin ring sign, low attenuation plaque, spotty calcifications, positive remodelling). Patients with overt and subclinical hyperthyroidism had more high-grade stenoses (39.2% vs 37.8% vs 24.2%; P = 0.007) and a higher coronary calcium score (456.5 vs 199.5 vs 155.9; P hyperthyroidism, followed by those with subclinical hyperthyroidism, had the most high-risk plaque features: napkin ring (21.6% vs 9.5% vs 6.0%, P hyperthyroid patients. Patients with subclinical and overt hyperthyroidism showed more high-grade coronary stenoses, plaque burden, and high-risk plaque features than patients with euthyroidism, which indicates that an increase of thyroid hormones might lead to coronary vascular degeneration and plaque instability. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  9. Postmortem-computed tomography and postmortem-computed tomography-angiography: a focused update.

    Science.gov (United States)

    Busardò, Francesco Paolo; Frati, Paola; Guglielmi, Giuseppe; Grilli, Giampaolo; Pinto, Antonio; Rotondo, Antonio; Panebianco, Valeria; Fineschi, Vittorio

    2015-09-01

    The use of multidetector CT (MDCT) represents a reality routinely used in several forensic institutes, for the numerous advantages that this diagnostic tool can provide; costs are becoming increasingly lower; data acquisition is always faster and once acquired may be revalued at any time. However, there are also some diagnostic limitations, for example, the visualization of the vascular system or a limited soft tissue contrast. In order to overcome these limitations, in recent years, contrast medium has been introduced in postmortem cases, with the development of several techniques of PMCT angiography (PMCTA) and standardized protocols to make them easily reproducible. The aim of this review is to highlight the advantages and pitfalls of PMCT and PMCTA in forensic investigation, taking into consideration the broad spectrum of applications both for natural and unnatural deaths and the numerous methods currently used. Secondly, in the light of the considerable progress in this field and the attempt to develop standardized protocols of PMCTA, the authors aim to evaluate the diagnostic value of PMCTA in comparison both to PMCT and conventional autopsy.

  10. Diagnostic performance of computed tomography angiography and contrast-enhanced magnetic resonance angiography in patients with critical limb ischaemia and intermittent claudication: systematic review and meta-analysis.

    Science.gov (United States)

    Jens, Sjoerd; Koelemay, Mark J W; Reekers, Jim A; Bipat, Shandra

    2013-11-01

    To evaluate the diagnostic performance of computed tomography angiography (CTA) and contrast-enhanced magnetic resonance angiography (CE-MRA) in detecting haemodynamically significant arterial stenosis or occlusion in patients with critical limb ischaemia (CLI) or intermittent claudication (IC). Medline and Embase were searched for studies comparing CTA or CE-MRA with digital subtraction angiography as a reference standard, including patients with CLI or IC. Outcome measures were aortotibial arterial stenosis of more than 50 % or occlusion. Methodological quality of studies was assessed using QUADAS. Out of 5,693 articles, 12 CTA and 30 CE-MRA studies were included, respectively evaluating 673 and 1,404 participants. Summary estimates of sensitivity and specificity were respectively 96 % (95 % CI, 93-98 %) and 95 % (95 % CI, 92-97 %) for CTA, and 93 % (95 % CI, 91-95 %) and 94 % (95 % CI, 93-96 %) for CE-MRA. Regression analysis showed that the prevalence of CLI in individual studies was not an independent predictor of sensitivity and specificity for either technique. Methodological quality of studies was moderate to good. CTA and CE-MRA are accurate techniques for evaluating disease severity of aortotibial arteries in patients with CLI or IC. No significant differences in the diagnostic performance of the two techniques between patients with CLI and IC were found. • Computed tomography and contrast-enhanced magnetic resonance angiography can both demonstrate arterial disease. • CTA and CE-MRA can both accurately evaluate arteries in peripheral arterial disease. • Diagnostic performances of critical limb ischaemia and intermittent claudication are not different. • Separate imaging technique of tibial arteries by CE-MRA is preferred. • CTA and CE-MRA can distinguish confidently between high-grade stenoses and occlusions.

  11. Noncontrast-Enhanced Magnetic Resonance Versus Computed Tomography Angiography in Preoperative Evaluation of Potential Living Renal Donors

    DEFF Research Database (Denmark)

    Blankholm, Anne Dorte; Pedersen, Bodil G; Østrat, Ernst Ø

    2015-01-01

    RATIONALE AND OBJECTIVES: Living renal donors undergo an extensive examination program. These examinations should be as safe, gentle, and patient friendly as possible. To compare computed tomography angiography (CTA) and an extensive magnetic resonance imaging (MRI) protocol without contrast agents......: (sensitivity60%/specifivity100%/accuracy 93%/Kappa = 0.72/P = 1), whereas CTA showed: (sensitivity 40%/specificity 96%/accuracy 87% Kappa = 0.43/P = 1). CONCLUSIONS: In conclusion, an optimized MRI protocol that includes noncontrast-enhanced magnetic resonance angiography can be substituted for CTA...

  12. Selective application of angiography for diagnosis of abdominal complaints (liver, pancreas and kidney) with reference to computed tomography and ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Hideo; Oishi, Hajime (Nara Medical Univ., Kashihara (Japan)); Kuroda, Chikazumi; Nakamura, Hitonobu

    1982-11-01

    Computed tomography (CT) and ultrasound (US) being used as the initial screening procedure for patients with abdominal complaints are contributory to discrimination of cystic lesions between solid and complex. Angiography should no longer be used for screening purpose and, furthermore, is not to be applied to most cases of not only the cystic lesions but also advanced hepatoma with portal tumor thrombosis as well as pancreatic cancer with liver metastasis diagnosed by CT or US. The angiography, on the other hand, should be restricted to such purposes as detection of small solid lesion, differentiation of inflammatory mass from neoplasma and determination of surgical indication, which CT and US are considered incapable of achieving.

  13. Catheter Angiography

    Medline Plus

    Full Text Available ... treat medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection is needed to produce pictures of blood vessels in the body. Angiography is performed using: x-rays with catheters computed tomography (CT) magnetic resonance imaging ( ...

  14. Catheter Angiography

    Medline Plus

    Full Text Available ... in patients after trauma. evaluate arteries feeding a tumor prior to surgery or other procedures such as ... supplying a small area of tissue or a tumor; this is called superselective angiography. Unlike computed tomography ( ...

  15. The application of optical coherence tomography angiography in uveitis and inflammatory eye diseases.

    Science.gov (United States)

    Pichi, Francesco; Sarraf, David; Arepalli, Sruthi; Lowder, Careen Y; Cunningham, Emmett T; Neri, Piergiorgio; Albini, Thomas A; Gupta, Vishali; Baynes, Kimberly; Srivastava, Sunil K

    2017-07-01

    Since its introduction in the early 1990s, optical coherence tomography (OCT) has evolved in resolution and technological advances, and in recent years its initial application of assessing the morphology of a tissue has been implemented by the study of its functional blood flow, through optical coherence tomography angiography (OCTA). This novel technique details capillary networks by comparing the amount of light returned from static and moving targets without the need for intravenous dye administration. While this imaging modality has been used for various ocular conditions, the application OCTA to uveitis conditions remains sparse. This review aims to establish the basis of OCTA and its current application to ocular inflammatory disorders, with an emphasis on monitoring progression and response to treatment, as well as predicting visual complications. In particular, this review explores the use of OCTA in iris vessel dilation seen in various forms of iritis, as a predictive factor for further episodes of inflammation. OCTA can also depict ischemia in the deep plexus layers of the retina and identify true choroicapillaris ischemia in cases of placoid diseases or masking of the indocyanine green dye, as in multiple evanescent white dot syndrome. In addition, OCTA can depict neovascularization in granulomatous disease of the retina or choroid not previously depicted with previous imaging methods. While OCTA provides several advancements in the imaging, management and prognosis of uveitis diseases, we emphasize that further studies are required to fully understand its application to these conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Evaluation of malposition of the branch pulmonary arteries using cardiovascular computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hui [Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, GuangZhou, GuangDong (China); Brigham and Women' s Hospital, Harvard Medical School, Cardiovascular Imaging Program, Department of Medicine (Division of Cardiovascular Medicine) and Radiology, Boston, MA (United States); Juan, Yu-Hsiang [Brigham and Women' s Hospital, Harvard Medical School, Cardiovascular Imaging Program, Department of Medicine (Division of Cardiovascular Medicine) and Radiology, Boston, MA (United States); Chang Gung Memorial Hospital, Linkou and Chang Gung University, Department of Medical Imaging and Intervention, Taoyuan (China); Wang, Qiushi; Huang, Hongfei; Yang, Lin [Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, GuangZhou, GuangDong (China); Xie, Zhaofeng [Guangdong Academy of Medical Sciences, Department of Pediatric Cardiology, Guangdong General Hospital, GuangZhou, GuangDong (China); Chen, Jimei; Zhang, Xiaoshen [Guangdong Academy of Medical Sciences, Department of Cardiovascular Surgery, Guangdong General Hospital, GuangZhou, GuangDong (China); Liang, Changhong [Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, GuangZhou, GuangDong (China); Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, Guangzhou (China); Chung, Taylor [Children' s Hospital and Research Center Oakland, Department of Diagnostic Imaging, Oakland, CA (United States); Kwong, Raymond Y.; Saboo, Sachin S. [Brigham and Women' s Hospital, Harvard Medical School, Cardiovascular Imaging Program, Department of Medicine (Division of Cardiovascular Medicine) and Radiology, Boston, MA (United States)

    2014-12-15

    To analyze 15 cases of malposition of branch pulmonary arteries (MBPA) for the hospital-based prevalence, clinical information, surgical outcome, imaging findings, associated cardiovascular and airway abnormalities on cardiovascular computed tomography angiography (CCTA). We retrospectively searched for patients with MBPA from our database consisting of patients referred for CCTA due to known or suspected congenital heart disease and also from all patients receiving chest computed tomography (CT) during the same time period. We analyzed the hospital-based prevalence, image findings, associated cardiovascular anomalies, airway compression, and recorded the clinical information and surgical outcome. Our study showed 15 patients with MBPA (hospital-based prevalence: 0.33 % among patients with congenital heart disease and 0.06 % in all patients receiving chest CT or CCTA). Classic type was more common than lesser type (67 % versus 33 %). All patients had associated cardiovascular anomalies, including aortic arch abnormalities (80 %) and secondary airway compression (33 %). Surgery was performed in 67 % of cardiovascular anomalies and 60 % of airway stenoses. MBPA has a hospital-based prevalence of 0.33 % among patients with congenital heart disease and 0.06 % in all patients receiving either chest CT or CCTA. CCTA can delineate the anatomy of MBPA, associated cardiovascular and airway abnormalities for preoperative evaluation. (orig.)

  17. 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

  18. Importance of oral fluid intake after coronary computed tomography angiography: An observational study

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Daiji [Department of Cardiology, Nagoya University Graduate School of Medicine (Japan); Department of Cardiology, Kami-iida Daiichi General Hospital, Nagoya (Japan); Isobe, Satoshi, E-mail: sisobe@med.nagoya-u.ac.jp [Department of Cardiology, Nagoya University Graduate School of Medicine (Japan); Department of Cardiology, Kami-iida Daiichi General Hospital, Nagoya (Japan); Sato, Kimihide; Ohashi, Toshio [Division of Radiology, Kami-iida Daiichi General Hospital, Nagoya (Japan); Fujiwara, Yuka; Ohyama, Hisato [Division of Nursing, Kami-iida Daiichi General Hospital, Nagoya (Japan); Ishii, Hideki; Murohara, Toyoaki [Department of Cardiology, Nagoya University Graduate School of Medicine (Japan)

    2011-01-15

    Background: The prevention of contrast-induced acute kidney injury (AKI) after coronary computed tomography angiography (CCTA) is important because patients referred for CCTA often need further contrast exposure such as an invasive coronary angiography. We aimed to examine the effects of oral volume intake on renal function in patients with preserved renal function referred for CCTA. Methods: We enrolled 180 patients who were referred for CCTA. The serum creatinine (SCr) and estimated glomerular filtration rate (eGFR) levels were measured before, 24 h, and a mean of 4.8 days after CCTA. The amount of unrestricted oral fluid intake for 24 h was checked. The patients were divided into two groups: 106 subjects with a rise in SCr after CCTA (group A); and 74 without (group B). Results: Significant correlations were observed between the amount of oral fluid intake and the percentage changes in SCr (%SCr) (r = -0.66, p < 0.0001) as well as the absolute changes in eGFR ({Delta}eGFR) (r = 0.65, p < 0.0001). The percentage of patients showing hemoglobin-A1c (HbA1c) {>=} 6.5% was greater in group A than in group B (29% vs. 18%, p < 0.001). Patients with HbA1c {>=} 6.5% showed higher %SCr and lower {Delta}eGFR compared to those without it. Multiple regression analysis revealed that the amount of oral fluid intake was the only independent predictor for a rise in SCr ({beta} = -0.731, p < 0.0001). Conclusion: Oral volume intake after CCTA is a very simple but important prophylactic procedure for contrast-induced AKI especially in diabetic patients.

  19. Multi-detector Computed Tomography Angiography of the Hepatic Artery in Liver Transplant Recipients

    Energy Technology Data Exchange (ETDEWEB)

    Boraschi, P.; Donati, F.; Cossu, M.C.; Gigoni, R.; Vignali, C.; Filipponi, F.; Bartolozzi, C.; Falaschi, F. [Pisa Univ. Hospital (Italy). 2nd Dept. of Radiology

    2005-08-01

    PURPOSE: To evaluate the ability of multi-detector row computed tomography angiography (CTA) in detecting hepatic artery complications in the follow-up of liver transplant patients, performing volume-rendering as reconstruction technique. MATERIAL AND METHODS: The anatomy of hepatic artery was studied in 27 liver transplant recipients with a four-row CT scanner using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 6-8 mm/s; spiral reconstruction time, 0.5 s; reconstruction interval, 0.5 mm; mAs, 160; kVp, 120. Before the study, the patients received 1000 ml of water as oral contrast agent to produce negative contrast in the stomach and the small bowel. A non-ionic contrast medium was infused intravenously at a rate of 5 ml/s with a bolus tracking system. Volume-rendering of hepatic artery was performed with the 3D Virtuoso software. RESULTS: The celiac trunk, the hepatic artery, and the right and left hepatic arteries were successfully displayed in high detail in all patients. Side branches, including small collaterals, and hepatic artery anastomosis could also be readily visualized. Volume-rendered CTA detected six hepatic artery stenoses, two hepatic artery thromboses, and two intrahepatic pseudoaneurysms. In two cases, CT detected hepatic artery stenosis with a diameter reduction of less than 50%, while digital subtraction angiography showed a normal artery. CONCLUSION: Volume-rendered multi-detector CTA is a promising non-invasive technique, since it allows images of high quality to be generated with excellent anatomical visualization of the hepatic artery and its complications in liver transplant recipients.

  20. Prognostic Value of Coronary Computed Tomography (CT) Angiography and Coronary Artery Calcium Score Performed Before Revascularization.

    Science.gov (United States)

    Fujimoto, Shinichiro; Kondo, Takeshi; Kumamaru, Kanako K; Shinozaki, Tomohiro; Takamura, Kazuhisa; Kawaguchi, Yuko; Matsumori, Rie; Hiki, Makoto; Miyauchi, Katsumi; Daida, Hiroyuki; Rybicki, Frank J

    2015-08-21

    Cardiac events after revascularization are equally attributable to recurrence at site of culprit lesions and development of nonculprit lesions. We evaluated the hypothesis that coronary computed tomography (CT) angiography and coronary artery calcium score (CACS) performed before revascularization predicts cardiac events after treatment. Among 2238 consecutive patients without known coronary artery disease who underwent coronary CT angiography and CACS, 359 patients underwent revascularization within 30 days after CT; in 337 of 359 (93.9%) follow-up clinical information was available. In addition to known cardiac risk factors, CT findings were evaluated as predictors of cardiac events after revascularization: CACS and the presence of CT-verified high-risk plaque (CT-HRP). Improvement of predictive accuracy by including CT findings was evaluated from a discrimination (Harrell's C-statistics) standpoint. During the follow-up period (median: 673, interquartile range: 47 to 1529 days), a total of 98 cardiac events occurred. Cox proportional hazard model revealed that age, diabetes, triglyceride, CACS, and nonculprit CT-HRP were significant predictors of overall cardiac events. Although not statistically significant, discriminatory power was greater for the model with CACS (C-stat: 63.2%) and the model with both CACS and CT-HRP (65.8%) compared to the model including neither CACS nor CT-HRP (60.7%). High CACS and the presence of nonculprit CT-HRP performed before revascularization are significant predictors of cardiac events after revascularization. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  1. Novel Application of Micro-Computerized Tomography for Morphologic Characterization of the Murine Penis.

    Science.gov (United States)

    O'Neill, Marisol; Huang, Gene O; Lamb, Dolores J

    2017-12-01

    The murine penis model has enriched our understanding of anomalous penile development. The morphologic characterization of the murine penis using conventional serial sectioning methods is labor intensive and prone to errors. To develop a novel application of micro-computerized tomography (micro-CT) with iodine staining for rapid, non-destructive morphologic study of murine penis structure. Penises were dissected from 10 adult wild-type mice and imaged using micro-CT with iodine staining. Images were acquired at 5-μm spatial resolution on a Bruker SkyScan 1272 micro-CT system. After images were acquired, the specimens were washed of any remaining iodine and embedded in paraffin for conventional histologic examination. Histologic and micro-CT measurements for all specimens were made by 2 independent observers. Measurements of penile structures were made on virtual micro-CT sections and histologic slides. The Lin concordance correlation coefficient demonstrated almost perfect strength of agreement for interobserver variability for histologic section (0.9995, 95% CI = 0.9990-0.9997) and micro-CT section (0.9982, 95% CI = 0.9963-0.9991) measurements. Bland-Altman analysis for agreement between the 2 modalities of measurement demonstrated mean differences of -0.029, 0.022, and -0.068 mm for male urogenital mating protuberance, baculum, and penile glans length, respectively. There did not appear to be a bias for overestimation or underestimation of measured lengths and limits of agreement were narrow. The enhanced ability offered by micro-CT to phenotype the murine penis has the potential to improve translational studies examining the molecular pathways contributing to anomalous penile development. The present study describes the first reported use of micro-CT with iodine staining for imaging the murine penis. Producing repeated histologic sections of identical orientation was limited by inherent imperfections in mounting and tissue sectioning, but this was

  2. Evaluation of acute chest pain in the emergency department: "triple rule-out" computed tomography angiography.

    Science.gov (United States)

    Yoon, Yeonyee E; Wann, Samuel

    2011-01-01

    Triage of patients with acute, potentially life-threatening chest pain is one of the most important issues currently facing physicians in the emergency department. Appropriate evaluation of these patients begins with a skilled assessment of the individual patient's presenting symptoms and a careful review of his or her history and physical examination, often followed by serial recording of electrocardiograms and measurement of serum biochemical markers such as troponin and d-dimer. Stress testing, often accompanied by rest and stress myocardial perfusion imaging or echocardiography, and other diagnostic testing such as radionuclide lung scanning and invasive angiography may be required. A rapid, accurate, and cost-effective approach for the evaluation of emergency department patients with chest pain is needed. Development of newer generations of multidetector computed tomographic (MDCT) scanners, which are capable not only of performing high-quality noninvasive coronary angiography, but also concurrent aortic and pulmonary angiography, has led to increased use of MDCT for the so-called "triple rule out." MDCT is used for the detection of 3 of the most common life-threatening causes of chest pain-coronary artery disease, acute aortic syndrome, and pulmonary emboli. While triple rule-out protocol can be very useful and potentially cost effective when used appropriately, concern has risen regarding the overuse of this technology, which could expose patients to unnecessary radiation and iodinated contrast. The triple rule-out protocol is most appropriate for patients who present with acute chest pain, but are judged to have low to intermediate increased risk for acute coronary syndrome, and whose chest pain symptoms might also be attributed to acute pathologic conditions of the aorta or pulmonary arteries. MDCT should not be used as a routine screening procedure. Continued technical improvements in acquisition speed and spatial resolution of computed tomography images

  3. 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 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 difference in 1 year primary patency (hazard ratio [HR] 0.95, 95

  4. High spatial resolution time-resolved magnetic resonance angiography of lower extremity tumors at 3T: Comparison with computed tomography angiography.

    Science.gov (United States)

    Wu, Gang; Jin, Teng; Li, Ting; Morelli, John; Li, Xiaoming

    2016-09-01

    The aim of this study was to compare diagnostic value of high spatial resolution time-resolved magnetic resonance angiography with interleaved stochastic trajectory (TWIST) using Gadobutrol to Computed tomography angiography (CTA) for preoperative evaluation of lower extremity tumors.This prospective study was approved by the institutional review board. Fifty consecutive patients (31 men, 19 women, age range 18-80 years, average age 42.7 years) with lower extremity tumors underwent TWIST magnetic resonance angiography (MRA) and CTA. Digital subtraction angiography was available for 8 patients. Image quality of MRA was compared with CTA by 2 radiologists according to a 4-point Likert scale. Arterial involvement by tumor was compared using kappa test between MRA and CTA. The ability to identify feeding arteries and arterio-venous fistulae (AVF) was compared using Wilcoxon signed rank test and McNemar test, respectively.Image quality of MRA and CTA was rated without a statistically significant difference (3.88 ± 0.37 vs. 3.97 ± 0.16, P = 0.135). Intramodality agreement was high for the identification of arterial invasion (kappa = 0.806 ± 0.073 for Reader 1, kappa = 0.805 ± 0.073 for Reader 2). Readers found AVF in 27 of 50 MRA cases and 14 of 50 CTA cases (P < 0.001). Mean feeding arteries identified with MRA were significantly more than that with CTA (2.08 ± 1.72 vs. 1.62 ± 1.52, P = .02).TWIST MRA is a reliable imaging modality for the assessment of lower extremity tumors. TWIST MRA is comparable to CTA for the identification of AVF and feeding arteries.

  5. The role of computerized tomography in the evaluation of gastrointestinal bleeding following negative or failed endoscopy: A review of current status

    Directory of Open Access Journals (Sweden)

    Stunell H

    2008-01-01

    Full Text Available Gastrointestinal bleeding remains an important cause for emergency hospital admission with a significant related morbidity and mortality. Bleeding may relate to the upper or lower gastrointestinal tracts and clinical history and examination may guide investigations to the more likely source of bleeding. The now widespread availability of endoscopic equipment has made a huge impact on the rapid identification of the bleeding source. However, there remains a large group of patients with negative or failed endoscopy, in whom additional techniques are required to identify the source of bleeding. In the past, catheter angiography and radionuclide red cell labeling techniques were the preferred ′next step′ modalities used to aid in identifying a bleeding source within the gastrointestinal tract. However, these techniques are time-consuming and of limited sensitivity and specificity. In addition, catheter angiography is a relatively invasive procedure. In recent years, computerized tomography (CT has undergone major technological advances in its speed, resolution, multiplanar techniques and angiographic abilities. It has allowed excellent visualization of the both the small and large bowel allowing precise anatomical visualization of many causes of gastrointestinal tract (GIT bleeding. In addition, recent advances in multiphasic imaging now allow direct visualization of bleeding into the bowel. In many centers CT has therefore become the ′next step′ technique in identifying a bleeding source within the GIT following negative or failed endoscopy in the acute setting. In this review article, we review the current literature and discuss the current status of CT as a modality in investigating the patient with GIT bleeding.

  6. Duplex ultrasound and computed tomography angiography in the follow-up of endovascular abdominal aortic aneurysm repair: a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Cantador, Alex Aparecido; Siqueira, Daniel Emilio Dalledone; Jacobsen, Octavio Barcellos; Baracat, Jamal; Pereira, Ines Minniti Rodrigues; Menezes, Fabio Hüsemann; Guillaumon, Ana Terezinha, E-mail: alex_cantador@yahoo.com.br [Universidade Estadual de Campinas (FCM/UNICAMP), Campinas, SP (Brazil). Faculdade de Ciencias Medicas

    2016-07-15

    Objective: To compare duplex ultrasound and computed tomography (CT) angiography in terms of their performance in detecting endoleaks, as well as in determining the diameter of the aneurysm sac, in the postoperative follow-up of endovascular abdominal aortic aneurysm repair. Materials and Methods: This was a prospective study involving 30 patients who had undergone endovascular repair of infrarenal aortoiliac aneurysms. Duplex ultrasound and CT angiography were performed simultaneously by independent radiologists. Measurements of the aneurysm sac diameter were assessed, and the presence or absence of endoleaks was determined. Results: The average diameter of the aneurysm sac, as determined by duplex ultrasound and CT angiography was 6.09 ± 1.95 and 6.27 ± 2.16 cm, respectively. Pearson's correlation coefficient showing a statistically significant correlation (R = 0.88; p < 0.01). Comparing the duplex ultrasound and CT angiography results regarding the detection of endoleaks, we found that the former had a negative predictive value of 92.59% and a specificity of 96.15%. Conclusion: Our results show that there is little variation between the two methods evaluated, and that the choice between the two would have no significant effect on clinical management. Duplex ultrasound could replace CT angiography in the postoperative follow-up of endovascular aneurysm repair of the infrarenal aorta, because it is a low-cost procedure without the potential clinical complications related to the use of iodinated contrast and exposure to radiation. (author)

  7. The accuracy of noncontrast spiral computerized tomography in detecting lucent renal stones: A case report and literature review

    OpenAIRE

    Adwan, Ayman; Binsaleh, Saleh

    2015-01-01

    Renal stones are one of the most common diseases in the urology field that are easily diagnosed by one of the standard imaging techniques. Noncontrast spiral computerized tomography (CT) can detect up to 95% of the renal, ureteric and bladder stones, especially those with calcium composition, and considered nowadays one of the most accurate methods for detecting undetectable stones by other modalities. We report a case of a 60-year-old female who presented with colicky right flank pain due to...

  8. An Anatomical Study of Maxillary-Zygomatic Complex Using Three-Dimensional Computerized Tomography-Based Zygomatic Implantation

    OpenAIRE

    Xu, Xiangliang; Zhao, Shijie; Liu, Hui; Sun, Zhipeng; Wang, Jianwei; Zhang, Weiguang

    2017-01-01

    Objective. To obtain anatomical data of maxillary-zygomatic complex based on simulating the zygomatic implantation using cadaver heads and three-dimensional computerized tomography (3D-CT). Methods. Simulating zygomatic implantation was performed using seven cadaver heads and 3D-CT images from forty-eight adults. After measuring the maxillary-zygomatic complex, we analyzed the position between the implantation path and the maxillary sinus cavity as well as the distance between the implantatio...

  9. Coronary computed tomography angiography - Tolerability of β-blockers and contrast media, and temporal changes in radiation dose

    DEFF Research Database (Denmark)

    Pedersen, Charlotte; Thomsen, Camilla F; Hosbond, Susanne Elisabeth

    2014-01-01

    Abstract Objective: To determine the risk of administration of β-blockers, contrast induced nephropathy (CIN) and trend in x-rays use, during coronary computed tomography angiography (CCTA). Methods: A total of 416 patients were referred for elective CCTA. To achieve a resting heart rate below 60.......0001. Conclusions: In terms of side effects to β-blockers and contrast media, there were no short term complications to CCTA. Furthermore the radiation dose was dramatically diminished over the last three years....

  10. Multidetector computerized tomography urography is more accurate than excretory urography for diagnosing transitional cell carcinoma of the upper urinary tract in adults with hematuria.

    Science.gov (United States)

    Wang, Li-Jen; Wong, Yon-Cheong; Huang, Chen-Chih; Wu, Cheng-Hsien; Hung, Sheng-Che; Chen, Huan-Wu

    2010-01-01

    It is debatable whether traditionally used excretory urography or the recently introduced multidetector computerized tomography urography is more accurate for diagnosing upper urinary tract transitional cell carcinoma. We compared accuracy measures of both methods for diagnosing upper urinary tract transitional cell carcinoma in adult patients with hematuria. We retrospectively analyzed consecutive adult patients with hematuria undergoing excretory urography and multidetector computerized tomography urography before any surgery, intervention or treatment from April 2004 to December 2006 in our hospital. The presence of upper urinary tract transitional cell carcinoma on excretory urography and multidetector computerized tomography urography was reviewed independently by 2 uroradiologists who were blinded to clinical information and other imaging results. Final diagnosis of upper urinary tract transitional cell carcinoma was confirmed by histological results. Measures of the diagnostic accuracy of excretory urography and multidetector computerized tomography urography for upper urinary tract transitional cell carcinoma were calculated and compared with reference to the final diagnosis. Of 34 men and 26 women with hematuria (mean age 60.73 +/- 12.95 years) 19 (31.7%) had a final diagnosis of 24 upper urinary tract transitional cell carcinomas. The sensitivity, specificity and accuracy of excretory urography were 0.750, 0.860 and 0.849, respectively. In contrast, the sensitivity, specificity and accuracy of multidetector computerized tomography urography were 0.958, 1.000 and 0.996, respectively. Overall the area under the receiver operating characteristic curve for multidetector computerized tomography urography was significantly larger than that for excretory urography (0.978 vs 0.815, p = 0.005). Multidetector computerized tomography urography is more sensitive, specific and accurate than excretory urography in the diagnosis of upper urinary tract transitional cell

  11. Correlations between computerized tomography of the head and motor developmental disturbances of children with cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.H. (Nagasaki Univ. (Japan). School of Medicine)

    1981-01-01

    Two hundred and eighty-two children with cerebral palsy (C.P.) and thirty-seven normal children were studied by computerized tomography (C.T.) of the head for finding out the correlations between the organic damage of the brain and the motor developmental disturbance. The abnormal findings of C.T. were: enlargement of the ventricular system, high density area, low density area and porencephalus, enlargement of the sulcus and anomaly of the medial structure. Enlargement of the ventricular system seemed to have correlation with spasticity; the portion and the extent of the enlargement corresponded to the affected extremities and the severity of the spasticity. Children of other types also showed various abnormal C.T. findings but, in general, less than that of spastic types. The prognosis of the motor development of C.P. children cannot be predicted by serial C.T. examinations strictly, because early treatment could cause improvement to that of these children. However, it is of worthy notice that C.T. is an effective method of helping to diagnose the motor developmental disturbance in earlier childhood.

  12. The approximate inversion as a reconstruction method in X-ray computerized tomography

    CERN Document Server

    Dietz, R L

    1999-01-01

    The mathematical model of the X-ray computerized tomography will be developed in the first chapter, the approximate inversion will be introduced, and the Radon Transform will be used as an example to demonstrate calculation of a reconstruction cone. In the second chapter, a reconstruction method for the parallel geometry is discussed, leading to derivation of the method for a fan-beam geometry. The approximate inversion calculated for the limited-angle case is presented as an example of incomplete data problems. As with complete data problems, numerical examples are given and the method is compared with existing other methods. 3D reconstruction is the topic of the third chapter. Although of no relevance in practice, a parallel geometry will be examined. No problems are encountered in transferring the reconstruction cone to the cone beam geometry, but only for a scanning curve which also is of no relevance in practice. A further reconstruction method is presented for curves fulfilling the so-called Tuy conditi...

  13. A modified conjugate gradient method based on the Tikhonov system for computerized tomography (CT).

    Science.gov (United States)

    Wang, Qi; Wang, Huaxiang

    2011-04-01

    During the past few decades, computerized tomography (CT) was widely used for non-destructive testing (NDT) and non-destructive examination (NDE) in the industrial area because of its characteristics of non-invasiveness and visibility. Recently, CT technology has been applied to multi-phase flow measurement. Using the principle of radiation attenuation measurements along different directions through the investigated object with a special reconstruction algorithm, cross-sectional information of the scanned object can be worked out. It is a typical inverse problem and has always been a challenge for its nonlinearity and ill-conditions. The Tikhonov regulation method is widely used for similar ill-posed problems. However, the conventional Tikhonov method does not provide reconstructions with qualities good enough, the relative errors between the reconstructed images and the real distribution should be further reduced. In this paper, a modified conjugate gradient (CG) method is applied to a Tikhonov system (MCGT method) for reconstructing CT images. The computational load is dominated by the number of independent measurements m, and a preconditioner is imported to lower the condition number of the Tikhonov system. Both simulation and experiment results indicate that the proposed method can reduce the computational time and improve the quality of image reconstruction. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  14. Numerical Modeling of Jointed Rock Under Compressive Loading Using X-ray Computerized Tomography

    Science.gov (United States)

    Yu, Qinglei; Yang, Shengqi; Ranjith, P. G.; Zhu, Wancheng; Yang, Tianhong

    2016-03-01

    As jointed rocks consist of joints embedded within intact rock blocks, the presence and geometrical fabric of joints have a great influence on the mechanical behavior of rock. With consideration of the actual spatial shape of joints, a numerical model is proposed to investigate the fracture evolution mechanism of jointed rocks. In the proposed model, computerized tomography (CT) scanning is first used to capture the microstructure of a jointed sandstone specimen, which is artificially fabricated by loading the intact sample until the residual strength, and then digital image processing (DIP) techniques are applied to characterize the geometrical fabric of joints from the CT images. A simple vectorization method is used to convert the microstructure based on a cross-sectional image into a layer of 3-D vectorized microstructure and the overall 3-D model of the jointed sandstone including the real spatial shape of the joints is established by stacking the layers in a specific sequence. The 3-D model is then integrated into a well-established code [three-dimensional Rock Failure Process Analysis, (RFPA3D)]. Using the proposed model, a uniaxial compression test of the jointed sandstone is simulated. The results show that the presence of joints can produce tensile stress zones surrounding them, which result in the fracture of jointed rocks under a relatively small external load. In addition, the spatial shape of the joints has a great influence on the fracture process of jointed rocks.

  15. Intellectual function, activities of daily living and computerized tomography of the brain in geriatric demented patients

    Energy Technology Data Exchange (ETDEWEB)

    Omura, Fumiaki; Ogura, Chikara; Kishimoto, Akira; Okubo, Masayo; Imamoto, Atsushi (Tottori Univ., Yonago (Japan). School of Medicine); Tsuchie, Harutaka; Sugihara, Kanichiro; Fujii, Shozo

    1984-09-01

    Thirty eight patients of geriatric dementia (mean age 74.9 years) were examined by computerized tomography (CT) and their intellectual functions and activities of daily living (ADL) were evaluated. CT was evaluated by both visual assessment method and direct measuring method. Intellectual function was evaluated by Jikei University dementia rating scale. ADL was evaluated by both Hasegawa's rating scale and Sengoku's rating scale. Results were as follows: significant influence by age was observed in intellectual functions and ADL of subjects above 75 years old. There were good correlations between the higher intellectual function, the better grooming and hygiene, and less needs of nursing care. The severe brain atrophy evaluated by the visual assessment method was correlated with the depressed level of intellectual function. When brain atrophy is mild despite high degree of dementia, reexamination should be made to explore somatic diseases inducing depression of mental activity. It also should be noted that sex and age difference is important in studying geriatric patients.

  16. Prospective comparison of computerized tomography and excretory urography in the initial evaluation of asymptomatic microhematuria.

    Science.gov (United States)

    Gray Sears, Christine L; Ward, John F; Sears, Stephen T; Puckett, Michael F; Kane, Christopher J; Amling, Christopher L

    2002-12-01

    The ideal imaging study for evaluation of the upper urinary tract in patients with microhematuria has been debated. We prospectively compared the diagnostic yield of computerized tomography (CT) to excretory urography (IVP) in the initial evaluation of asymptomatic microhematuria. Between December 1998 and June 2001, 115 patients presenting with asymptomatic microhematuria underwent CT and IVP before cystoscopy. Helical CT images with 5 mm. adrenal and kidney slices with and without contrast material were followed by delayed 5 mm. ureteral contrast images through the bladder base. Each CT and IVP was examined by a radiologist who was blinded to the result of the other imaging study. Diagnostic yields of the imaging techniques were compared using the test of 2 proportions and chi-square analysis. Radiographic abnormalities were noted on CT or IVP in 38 patients. Sensitivity was 100% for CT and 60.5% for IVP, and specificity 97.4% for CT and 90.9% for IVP. CT accuracy was 98.3% compared to IVP accuracy which was 80.9% (p <0.001). A total of 40 nonurological diagnoses were made by CT, including 3 abdominal aortic aneurysms and 1 iliac artery aneurysm. No additional diagnoses were made by IVP. Fewer additional radiographic studies were recommended after CT than after IVP. The use of CT in the initial evaluation of asymptomatic microhematuria results in better diagnostic yield. In addition, more nonurological diagnoses can be made and less additional radiography is needed to confirm a diagnosis.

  17. Survey radiography and computerized tomography imaging of the thorax in female dogs with mammary tumors

    Directory of Open Access Journals (Sweden)

    Giordano Tatiana

    2010-03-01

    Full Text Available Abstract Background Accurate early diagnosis of lung metastases is important for establishing therapeutic measures. Therefore, the present study aimed to compare survey thoracic radiographs and computerized tomography (CT scans to specifically identify lung metastases in female dogs with mammary tumors. Methods Twenty-one female dogs, weighing 3 to 34 kg and aged from 5 years to 14 years and 10 months, with mammary tumors were studied. In all dogs before the imaging examinations, fine-needle aspiration cytology of the mammary tumors was performed to confirm the diagnosis. Three-view thoracic radiographs were accomplished: right lateral, left lateral and ventrodorsal views. Sequential transverse images of the thorax were acquired on a spiral Scanner, before and after intravenous bolus injection of nonionic iodine contrast. Soft-tissue and lung windows were applied. All the mammary tumors were surgically removed and examined histologically. Results The correlation between the cytological and histological results regarding presence of malignancy was observed in only 17 cases. In radiographic examinations, no dog displayed signs of lung metastases or thorax chest lesions. CT detected lung metastasis in two cases, while small areas of lung atelectasis located peripherally were found in 28.57% of the dogs. Conclusion In this study population, spiral CT showed higher sensitivity than chest radiographies to detect lung metastasis; this indicates that CT should be performed on all female dogs with malignant mammary tumors.

  18. The detection accuracies for proximal caries by cone-beam computerized tomography, film, and phosphor plates.

    Science.gov (United States)

    Zhang, Zhi-ling; Qu, Xing-min; Li, Gang; Zhang, Zu-yan; Ma, Xu-chen

    2011-01-01

    To evaluate the accuracy of cone-beam computerized tomography (CBCT) for the detection of noncavitated proximal caries and to compare the detection accuracies of 2 CBCT imaging systems with those based on plain-film radiographs and phosphor-plate images. Test radiographs of 39 noncavitated unrestored human permanent teeth were obtained with film, phosphor-plate, ProMax 3D, and Kodak 9000 3D imaging systems. Seven observers used a 5-level scale to evaluate test images for the presence of proximal caries. With histologic examination serving as the reference standard, observer performances were assessed with receiver operating characteristic (ROC) curves, and the areas under the ROC curves (A(z) values) for the observers, and modalities were analyzed with a repeated-measures analysis of variance. The mean A(z) values for film, phosphor plates, ProMax 3D, and Kodak 9000 3D imaging systems were 0.541, 0.523, 0.528, and 0.525, respectively (P = .763). For detecting subtle noncavitated proximal caries, the detection accuracy with the CBCT images was little better than chance performance and was similar to that with phosphor plate- and film-based intraoral images. Copyright © 2011 Mosby, Inc. All rights reserved.

  19. Multidetector computed tomography angiography of the celiac trunk and hepatic arterial system: normal anatomy and main variants

    Energy Technology Data Exchange (ETDEWEB)

    Araujo-Neto, Severino Aires; Mello-Junior, Carlos Fernando de; Franca, Henrique Almeida; Duarte, Claudia Martina Araujo; Borges, Rafael Farias; Magalhaes, Ana Guardiana Ximenes de, E-mail: severinoaires@hotmail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)

    2016-01-15

    Although digital angiography remains as the gold standard for imaging the celiac arterial trunk and hepatic arteries, multidetector computed tomography in association with digital images processing by software resources represents a useful tool particularly attractive for its non invasiveness. Knowledge of normal anatomy as well as of its variations is helpful in images interpretation and to address surgical planning on a case-by-case basis. The present essay illustrates several types of anatomical variations of celiac trunk, hepatic artery and its main branches, by means of digitally reconstructed computed tomography images, correlating their prevalence in the population with surgical implications. (author)

  20. Influence of Adaptive Statistical Iterative Reconstruction on coronary plaque analysis in coronary computed tomography angiography.

    Science.gov (United States)

    Precht, Helle; Kitslaar, Pieter H; Broersen, Alexander; Dijkstra, Jouke; Gerke, Oke; Thygesen, Jesper; Egstrup, Kenneth; Lambrechtsen, Jess

    The purpose of this study was to study the effect of iterative reconstruction (IR) software on quantitative plaque measurements in coronary computed tomography angiography (CCTA). Thirty patients with a three clinical risk factors for coronary artery disease (CAD) had one CCTA performed. Images were reconstructed using FBP, 30% and 60% adaptive statistical IR (ASIR). Coronary plaque analysis was performed as per patient and per vessel (LM, LAD, CX and RCA) measurements. Lumen and vessel volumes and plaque burden measurements were based on automatic detected contours in each reconstruction. Lumen and plaque intensity measurements and HU based plaque characterization were based on corrected contours copied to each reconstruction. No significant changes between FBP and 30% ASIR were found except for lumen- (-2.53 HU) and plaque intensities (-1.28 HU). Between FBP and 60% ASIR the change in total volume showed an increase of 0.94%, 4.36% and 2.01% for lumen, plaque and vessel, respectively. The change in total plaque burden between FBP and 60% ASIR was 0.76%. Lumen and plaque intensities decreased between FBP and 60% ASIR with -9.90 HU and -1.97 HU, respectively. The total plaque component volume changes were all small with a maximum change of -1.13% of necrotic core between FBP and 60% ASIR. Quantitative plaque measurements only showed modest differences between FBP and the 60% ASIR level. Differences were increased lumen-, vessel- and plaque volumes, decreased lumen- and plaque intensities and a small percentage change in the individual plaque component volumes. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  1. Prospectively electrocardiogram-triggered high-pitch spiral acquisition coronary computed tomography angiography for assessment of biodegradable vascular scaffold expansion: Comparison with optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    D’Alfonso, Maria Grazia [Interventional Cardiology Unit University Of Florence, Heart and Vessels department, AOU Careggi, Florence (Italy); Mattesini, Alessio, E-mail: amattesini@gmail.com [Interventional Cardiology Unit University Of Florence, Heart and Vessels department, AOU Careggi, Florence (Italy); Meucci, Francesco [Interventional Cardiology Unit University Of Florence, Heart and Vessels department, AOU Careggi, Florence (Italy); Acquafresca, Manlio [Radiology Unit 4, Radiology Department, AOU Careggi, Florence (Italy); Gensini, Gian Franco; Valente, Serafina [Interventional Cardiology Unit University Of Florence, Heart and Vessels department, AOU Careggi, Florence (Italy)

    2014-11-15

    BVS polymeric struts are transparent to the light so that the vessel wall contour can be easily visualized using optical coherence tomography (OCT). Therefore OCT represents a unique tool for both the evaluation of the resorption process and for the assessment of acute BVS mechanical failure. Similarly, the metal-free struts allow unrestricted coronary computed tomography angiography (CCTA), thus this non invasive method might become the gold standard for a non invasive assessment of BVS. In this case we show the ability of CCTA, performed with a low X-Ray dose, to provide a good evaluation of scaffold expansion. The quantitative measurements were in agreement with those obtained with OCT.

  2. CAD-RADS - a new clinical decision support tool for coronary computed tomography angiography.

    Science.gov (United States)

    Foldyna, Borek; Szilveszter, Bálint; Scholtz, Jan-Erik; Banerji, Dahlia; Maurovich-Horvat, Pál; Hoffmann, Udo

    2017-11-07

    Coronary computed tomography angiography (CTA) has been established as an accurate method to non-invasively assess coronary artery disease (CAD). The proposed 'Coronary Artery Disease Reporting and Data System' (CAD-RADS) may enable standardised reporting of the broad spectrum of coronary CTA findings related to the presence, extent and composition of coronary atherosclerosis. The CAD-RADS classification is a comprehensive tool for summarising findings on a per-patient-basis dependent on the highest-grade coronary artery lesion, ranging from CAD-RADS 0 (absence of CAD) to CAD-RADS 5 (total occlusion of a coronary artery). In addition, it provides suggestions for clinical management for each classification, including further testing and therapeutic options. Despite some limitations, CAD-RADS may facilitate improved communication between imagers and patient caregivers. As such, CAD-RADS may enable a more efficient use of coronary CTA leading to more accurate utilisation of invasive coronary angiograms. Furthermore, widespread use of CAD-RADS may facilitate registry-based research of diagnostic and prognostic aspects of CTA. • CAD-RADS is a tool for standardising coronary CTA reports. • CAD-RADS includes clinical treatment recommendations based on CTA findings. • CAD-RADS has the potential to reduce variability of CTA reports.

  3. 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 ASIR improved the subjective image quality of parameter sharpness and, objectively, reduced noise and increased CNR.

  4. Automatic detection of carotid arteries in computed tomography angiography: a proof of concept protocol.

    Science.gov (United States)

    Dos Santos, Florentino Luciano Caetano; Joutsen, Atte; Paci, Michelangelo; Salenius, Juha; Eskola, Hannu

    2016-08-01

    Atherosclerosis is one of the leading causes of mortality in the western world. Computed tomography angiography (CTA) is the conventional imaging method used for pre-surgery assessment of the blood flow within the carotid vessel. In this paper, we present a proof of concept of a novel, fast and operator independent protocol for the automatic detection (seeding) of the carotid arteries in CTA in the thorax and upper neck region. The dataset is composed of 14 patients' CTA images of the neck region. The performance of this method is compared with manual seeding by four trained operators. Inter-operator variation is also assessed based on the dataset. The minimum, average and maximum coefficient of variation among the operators was (0, 2, 5 %), respectively. The performance of our method is comparable with the state of the art alternative, presenting a detection rate of 75 and 71 % for the lowest and uppermost image levels, respectively. The mean processing time is 167 s per patient versus 386 s for manual seeding. There are no significant differences between the manual and automatic seed positions in the volumes (p = 0.29). A fast, operator independent protocol was developed for the automatic detection of carotid arteries in CTA. The results are encouraging and provide the basis for the creation of automatic detection and analysis tools for carotid arteries.

  5. Strip-based registration of serially acquired optical coherence tomography angiography

    Science.gov (United States)

    Heisler, Morgan; Lee, Sieun; Mammo, Zaid; Jian, Yifan; Ju, MyeongJin; Merkur, Andrew; Navajas, Eduardo; Balaratnasingam, Chandrakumar; Beg, Mirza Faisal; Sarunic, Marinko V.

    2017-03-01

    The visibility of retinal microvasculature in optical coherence tomography angiography (OCT-A) images is negatively affected by the small dimension of the capillaries, pulsatile blood flow, and motion artifacts. Serial acquisition and time-averaging of multiple OCT-A images can enhance the definition of the capillaries and result in repeatable and consistent visualization. We demonstrate an automated method for registration and averaging of serially acquired OCT-A images. Ten OCT-A volumes from six normal control subjects were acquired using our prototype 1060-nm swept source OCT system. The volumes were divided into microsaccade-free en face angiogram strips, which were affine registered using scale-invariant feature transform keypoints, followed by nonrigid registration by pixel-wise local neighborhood matching. The resulting averaged images were presented of all the retinal layers combined, as well as in the superficial and deep plexus layers separately. The contrast-to-noise ratio and signal-to-noise ratio of the angiograms with all retinal layers (reported as average±standard deviation) increased from 0.52±0.22 and 19.58±4.04 dB for a single image to 0.77±0.25 and 25.05±4.73 dB, respectively, for the serially acquired images after registration and averaging. The improved visualization of the capillaries can enable robust quantification and study of minute changes in retinal microvasculature.

  6. The quantitative measurements of foveal avascular zone using optical coherence tomography angiography in normal volunteers.

    Science.gov (United States)

    Ghassemi, Fariba; Mirshahi, Reza; Bazvand, Fatemeh; Fadakar, Kaveh; Faghihi, Houshang; Sabour, Siamak

    2017-12-01

    To provide normative data of foveal avascular zone (FAZ) and thickness. In this cross-sectional study both eyes of each normal subject were scanned with optical coherence tomography angiography (OCTA) for foveal superficial and deep avascular zone (FAZ) and central foveal thickness (CFT) and parafoveal thickness (PFT). Out of a total of 224 eyes of 112 volunteers with a mean age of 37.03 (12-67) years, the mean superficial FAZ area was 0.27 mm2, and deep FAZ area was 0.35 mm2 (P < 0.001), with no difference between both eyes. Females had a larger superficial (0.32 ± 0.11 mm2 versus 0.23 ± 0.09 mm2) and deep FAZ (0.40 ± 0.14 mm2 versus 0.31 ± 0.10 mm2) (P < 0.001) than males. By multivariate linear regression analysis, in normal eyes, superficial FAZ area varied significantly with the gender, CFT, and deep FAZ. Deep FAZ varied with the gender and CFT. The gender and CFT influence the size of normal superficial and deep FAZ of capillary network.

  7. Male Gender and Arterial Hypertension are Plaque Predictors at Coronary Computed Tomography Angiography

    Science.gov (United States)

    Oliveira, Joselina Luzia Menezes; Hirata, Mario Hiroyuki; Sousa, Amanda Guerra de Moraes Rego; Gabriel, Fabíola Santos; Hirata, Thiago Dominguez Crespo; Tavares, Irlaneide da Silva; Melo, Luiza Dantas; Dória, Fabiana de Santana; Sousa, Antônio Carlos Sobral; Pinto, Ibraim Masciarelli Francisco

    2015-01-01

    Background Systemic Arterial Hypertension (SAH) is one of the main risk factors for Coronary Artery Disease (CAD), in addition to male gender. Differences in coronary artery lesions between hypertensive and normotensive individuals of both genders at the Coronary Computed Tomography Angiography (CCTA) have not been clearly determined. Objective To Investigate the calcium score (CS), CAD extent and characteristics of coronary plaques at CCTA in men and women with and without SAH. Methods Prospective cross-sectional study of 509 patients undergoing CCTA for CAD diagnosis and risk stratification, from November 2011 to December 2012, at Instituto de Cardiologia Dante Pazzanese. Individuals were stratified according to gender and subdivided according to the presence (HT +) or absence (HT-) of SAH. Results HT+ women were older (62.3 ± 10.2 vs 57.8 ± 12.8, p = 0.01). As for the assessment of CAD extent, the HT+ individuals of both genders had significant CAD, although multivessel disease is more frequent in HT + men. The regression analysis for significant CAD showed that age and male gender were the determinant factors of multivessel disease and CS ≥ 100. Plaque type analysis showed that SAH was a predictive risk factor for partially calcified plaques (OR = 3.9). Conclusion Hypertensive men had multivessel disease more often than women. Male gender was a determinant factor of significant CAD, multivessel disease, CS ≥ 100 and calcified and partially calcified plaques, whereas SAH was predictive of partially calcified plaques. PMID:25861034

  8. Computer-aided analysis of 64-slice coronary computed tomography angiography: a comparison with manual interpretation

    Directory of Open Access Journals (Sweden)

    Donna Kam

    2013-01-01

    Full Text Available Coronary computed tomography angiography (CCTA is increasingly used for the assessment of coronary heart disease (CHD in symptomatic patients. Software applications have recently been developed to facilitate efficient and accurate analysis of CCTA. This study aims to evaluate the clinical application of computer-aided diagnosis (CAD software for the detection of significant coronary stenosis on CCTA in populations with low (8%, moderate (13%, and high (27% CHD prevalence. A total of 341 consecutive patients underwent 64-slice CCTA at 3 clinical sites in the United States. CAD software performed automatic detection of significant coronary lesions (>50% stenosis. CAD results were then compared to the consensus manual interpretation of 2 imaging experts. Data analysis was conducted for each patient and segment. The CAD had 100% sensitivity per patient across all 3 clinical sites. Specificity in the low, moderate, and high CHD prevalence populations was 64%, 41%, and 38%, respectively. The negative predictive value at the 3 clinical sites was 100%. The positive predictive value was 22%, 21%, and 38% for the low, moderate, and high CHD prevalence populations, respectively. This study demonstrates the utility of CAD software in 3 distinct clinical settings. In a low-prevalence population, such as seen in the emergency department, CAD can be used as a Computer-Aided Simple Triage tool to assist in diagnostic delineation of acute chest pain. In a higher prevalence population, CAD software is useful as an adjunct for both the experienced and inexperienced reader.

  9. Acute Retinal Pigment Epitheliitis: Spectral Domain Optical Coherence Tomography, Fluorescein Angiography, and Autofluorescence Findings

    Directory of Open Access Journals (Sweden)

    Tuğba Aydoğan

    2015-01-01

    Full Text Available A 17-year-old presented with central and paracentral scotomas in his right eye for one week. There was no remarkable medical or ocular history. Blood analyses were within normal range. At presentation both eyes’ best-corrected visual acuities were 20/20. Slit-lamp examination result was normal. Fundus examination revealed yellow-white hypopigmented areas in the macula. Fluorescein angiography (FA showed hypofluorescence surrounded by ring of hyperfluorescence. Fundus autofluorescence (FAF was slightly increased. Spectral domain optical coherence tomography (SD-OCT showed disruption of IS/OS junction with expansion of abnormal hyperreflectivity from retinal pigment epithelium to the outer nuclear layer (ONL. One month later fundus examination showed disappearance of the lesions. FA revealed transmission hyperfluorescence. FAF showed increased autofluorescence and pigment clumping. Hyperreflective band in SD-OCT disappeared. Loss of photoreceptor segment layers was observed in some of the macular lesions. The diagnosis of acute retinal pigment epitheliitis can be challenging after disappearance of fundus findings. FA, FAF, and SD-OCT are important tests for diagnosis after resolution of the disease.

  10. Visualization of micro-capillaries using optical coherence tomography angiography with and without adaptive optics.

    Science.gov (United States)

    Salas, Matthias; Augustin, Marco; Ginner, Laurin; Kumar, Abhishek; Baumann, Bernhard; Leitgeb, Rainer; Drexler, Wolfgang; Prager, Sonja; Hafner, Julia; Schmidt-Erfurth, Ursula; Pircher, Michael

    2017-01-01

    The purpose of this work is to investigate the benefits of adaptive optics (AO) technology for optical coherence tomography angiography (OCTA). OCTA has shown great potential in non-invasively enhancing the contrast of vessels and small capillaries. Especially the capability of the technique to visualize capillaries with a lateral extension that is below the transverse resolution of the system opens unique opportunities in diagnosing retinal vascular diseases. However, there are some limitations of this technology such as shadowing and projection artifacts caused by overlying vasculature or the inability to determine the true extension of a vessel. Thus, the evaluation of the vascular structure and density based on OCTA alone can be misleading. In this paper we compare the performance of AO-OCT, AO-OCTA and OCTA for imaging retinal vasculature. The improved transverse resolution and the reduced depth of focus of AO-OCT and AO-OCTA greatly reduce shadowing artifacts allowing for a better differentiation and segmentation of different vasculature layers of the inner retina. The comparison is done on images recorded in healthy volunteers and in diabetic patients with distinct pathologies of the retinal microvasculature.

  11. Isolated unilateral absence of the right pulmonary artery in two cats visualized by computed tomography angiography

    Directory of Open Access Journals (Sweden)

    Tyler JM Jordan

    2016-10-01

    Full Text Available Case series summary Two cats were evaluated for progressive exercise intolerance, dyspnea and unilateral infiltrate of the left lung. Computed tomography angiography (CTA revealed absence of the right pulmonary artery in both cats with systemic arterial collateral vessels perfusing the right segmental pulmonary arteries. In one case, the collateral vessels arose from the esophageal artery, while in the other case they derived off the right costocervical trunk. One cat was diagnosed with pulmonary hypertension and was euthanized owing to progressive respiratory distress despite medical management with sildenafil, pimobendan, clopidogrel and furosemide. The other cat, without echocardiographic evidence of pulmonary hypertension, was successfully managed with furosemide and enalapril for more than 4 years. Relevance and novel information CTA allowed visualization of a rare congenital heart malformation, unilateral absence of the right pulmonary artery, in two cats and accurately characterized the source of collateral blood supply to the affected lung. Severe pulmonary hypertension may be a negative prognostic factor in cats with this condition as medical therapy in the cat without evidence of pulmonary hypertension resolved clinical signs, while the cat with severe pulmonary hypertension died from the disease.

  12. Application study of 640-slice computed tomography low dose coronary angiography

    Directory of Open Access Journals (Sweden)

    Ziqiao Lei

    2015-01-01

    Full Text Available Objective: The aim was to explore image quality and radiation dose in patients with different heart rates in 640-slice volume computed tomography (CT coronary angiography by using tube voltage of 100 kV. Materials and Methods: The 220 consecutive patients clinically suspected or confirmed of coronary artery disease were divided into three groups: 67 cases in 1 beat group (heart rate 80 bpm. When scanning was completed, the best phase for coronary arteries would be chosen. Various postprocessing reconstructions of coronary arteries and branches, such as volume reconstruction (VR, maximum density projection, multiplanar reconstruction, curved surface reconstruction, were used. We classified image quality and made statistical analysis according to 4-grades method. We also compared scalability of coronary arterial segments and radiation doses between the groups. Results: There were no significant differences in the scalability of coronary arterial segments between the groups. Effective radiation doses of the three groups were (2.5±0.8 mSv, (8.4±3.1 mSv and (11.2±3.8mSv. The radiation doses between the groups showed statistical difference (P < 0.05. Conclusion: 640-slice volume CT can be adapted to changes during heart rate, and ensure the image quality under the condition of 100 kV, and radiation doses were significantly reduced in patients with heart rate <65 bpm.

  13. Detailed Vascular Anatomy of the Human Retina by Projection-Resolved Optical Coherence Tomography Angiography

    Science.gov (United States)

    Campbell, J. P.; Zhang, M.; Hwang, T. S.; Bailey, S. T.; Wilson, D. J.; Jia, Y.; Huang, D.

    2017-02-01

    Optical coherence tomography angiography (OCTA) is a noninvasive method of 3D imaging of the retinal and choroidal circulations. However, vascular depth discrimination is limited by superficial vessels projecting flow signal artifact onto deeper layers. The projection-resolved (PR) OCTA algorithm improves depth resolution by removing projection artifact while retaining in-situ flow signal from real blood vessels in deeper layers. This novel technology allowed us to study the normal retinal vasculature in vivo with better depth resolution than previously possible. Our investigation in normal human volunteers revealed the presence of 2 to 4 distinct vascular plexuses in the retina, depending on location relative to the optic disc and fovea. The vascular pattern in these retinal plexuses and interconnecting layers are consistent with previous histologic studies. Based on these data, we propose an improved system of nomenclature and segmentation boundaries for detailed 3-dimensional retinal vascular anatomy by OCTA. This could serve as a basis for future investigation of both normal retinal anatomy, as well as vascular malformations, nonperfusion, and neovascularization.

  14. Assessment of the cortical artery using computed tomography angiography for bypass surgery in moyamoya disease.

    Science.gov (United States)

    Suzuki, Hime; Mikami, Takeshi; Komatsu, Katsuya; Noshiro, Shouhei; Miyata, Kei; Hirano, Toru; Wanibuchi, Masahiko; Mikuni, Nobuhiro

    2017-04-01

    Computed tomography angiography (CTA) is often used to assess the vascular status in moyamoya disease. The purpose of the study is to identify the characteristics of cortical arteries (M4) of moyamoya disease on CTA; the clinical significance of which is also discussed. A total of 38 hemispheric sides of 27 patients with moyamoya disease were included in this study. The number of M4 was visualized on CTA using cortical surface imaging and compared between the moyamoya disease group and the non-moyamoya disease group or the control group. Then, the clinical and radiological factors associated with the number of M4, the distribution of M4, and collateral circulation were examined. The number of M4 was lower in the moyamoya disease group than in the non-moyamoya disease group and in the control group (p moyamoya disease (p moyamoya disease (p moyamoya disease differed from that of the non-moyamoya disease group, and the distribution patterns of M4 might be influenced by collateral circulation. It is thus essential to recognize M4 to assess the recipient artery so as to ensure superficial temporal artery-middle cerebral artery bypass.

  15. Computed tomography versus invasive coronary angiography: design and methods of the pragmatic randomised multicentre DISCHARGE trial

    Energy Technology Data Exchange (ETDEWEB)

    Napp, Adriane E.; Haase, Robert; Schuetz, Georg M.; Rief, Matthias; Katzer, Christoph; Dewey, Marc [Charite - Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Laule, Michael; Dreger, Henryk [Charite - Universitaetsmedizin Berlin, Department of Cardiology, Berlin (Germany); Feuchtner, Gudrun [Medical University Innsbruck, Department of Radiology, Innsbruck (Austria); Friedrich, Guy [Medical University Innsbruck, Department of Cardiology, Innsbruck (Austria); Spacek, Miloslav [University Hospital Motol, Department of Cardiology, Prague (Czech Republic); Suchanek, Vojtech [University Hospital Motol, Department of Radiology, Prague (Czech Republic); Fuglsang Kofoed, Klaus [Rigshospitalet Region Hovedstaden, Department of Radiology and Department of Cardiology, Copenhagen (Denmark); Engstroem, Thomas [Rigshospitalet Region Hovedstaden, Department of Cardiology, Copenhagen (Denmark); Schroeder, Stephen; Drosch, Tanja [ALB FILS KLINIKEN GmbH, Department of Cardiology, Goeppingen (Germany); Gutberlet, Matthias [University of Leipzig Heart Centre, Department of Radiology, Leipzig (Germany); Woinke, Michael [University of Leipzig Heart Centre, Department of Cardiology, Leipzig (Germany); Maurovich-Horvat, Pal; Merkely, Bela [Semmelweis University, MTA-SE Cardiovascular Imaging Center, Heart and Vascular Center, Budapest (Hungary); Donnelly, Patrick [Southeastern Health and Social Care Trust, Department of Cardiology, Belfast (United Kingdom); Ball, Peter [Southeastern Health and Social Care Trust, Department of Radiology, Belfast (United Kingdom); Dodd, Jonathan D. [St. Vincent' s University Hospital and National University of Ireland, Department of Radiology, Dublin (Ireland); Quinn, Martin [St. Vincent' s University Hospital, Department of Cardiology, Dublin (Ireland); Saba, Luca [Azienda Ospedaliero Universitaria di Cagliari, Department of Radiology, Monserrato (Italy); Porcu, Maurizio [Azienda Ospedaliera Brotzu, Department of Cardiology, Cagliari (Italy); Francone, Marco [Sapienza University of Rome, Department of Radiology, Rome (Italy); Mancone, Massimo [Sapienza University of Rome, Department of Cardiovascular, Respiratory, Nephrology, Anesthesiology and Geriatric Sciences, Rome (Italy); Erglis, Andrejs [Paul Stradins Clinical University Hospital, Department of Cardiology, Riga (Latvia); Zvaigzne, Ligita [Paul Stradins Clinical University Hospital, Department of Radiology, Riga (Latvia); Jankauskas, Antanas [Lithuanian University of Health Sciences, Department of Radiology, Kaunas (Lithuania); Sakalyte, Gintare [Lithuanian University of Health Sciences, Department of Cardiology, Kaunas (Lithuania); Haran, Tomasz [Wojewodzki Szpital Specjalistyczny We Wroclawiu, Department of Radiology, Wroclaw (Poland); Ilnicka-Suckiel, Malgorzata [Wojewodzki Szpital Specjalistyczny We Wroclawiu, Department of Cardiology, Wroclaw (Poland); Bettencourt, Nuno; Gama-Ribeiro, Vasco [Centro Hospitalar de Vila Nova de Gaia, Department of Cardiology, Vila Nova de Gaia (Portugal); Condrea, Sebastian; Benedek, Imre [Cardio Med Medical Center, Department of Cardiology, Targu-Mures (Romania); Cemerlic Adjic, Nada [Institute of Cardiovascular Diseases of Vojvodina, Department of Cardiology, Novi Sad, Sremska Kamenica (Serbia); Adjic, Oto [Institute of Cardiovascular Diseases of Vojvodina, Radiology Department Imaging Center, Novi Sad, Sremska Kamenica (Serbia); Rodriguez-Palomares, Jose; Garcia del Blanco, Bruno [Universitat Autonoma de Barcelona, Department of Cardiology (Barcelona Spain), Hospital Universitari Vall d' Hebron, Institut de Recerca (VHIR), Barcelona (ES); Roditi, Giles; Berry, Colin [University of Glasgow, Institute of Cardiovascular and Medical Sciences, Glasgow (GB); Davis, Gershan [Aintree University Hospital, Department of Cardiology, Liverpool (GB); Thwaite, Erica [Aintree University Hospital, Department of Radiology, Liverpool (GB); Knuuti, Juhani [Turku University Hospital and University of Turku, Turku PET Centre, Turku (FI); Pietilae, Mikko [Turku University Hospital, Heart Centre, Turku (FI); Kepka, Cezary [The Institute of Cardiology in Warsaw, Department of Radiology, Warsaw (PL); Kruk, Mariusz [The Institute of Cardiology in Warsaw, Department of Cardiology, Warsaw (PL); Vidakovic, Radosav; Neskovic, Aleksandar N. [Clinical Hospital Center Zemun, Department of Cardiology, Belgrade-Zemun (RS); Diez, Ignacio [Basurto University Hospital, Department of Cardiology, Bilbao (ES); Lecumberri, Inigo [Basurto University Hospital, Department of Radiology, Bilbao (ES); Geleijns, Jacob [Leiden University Medical Center, Department of Radiology, Leiden (NL); Kubiak, Christine [European Clinical Research Infrastructure Network (ECRIN-ERIC), Management Office, Paris (FR); Strenge-Hesse, Anke [University Cologne, European Clinical Research Infrastructure Network (ECRIN-ERIC), National ECRIN office/KKS Network, Cologne (DE); Do, The-Hoang; Froemel, Felix [Charite - Universitaetsmedizin Berlin, Clinical Coordinating Centre, Berlin (DE); Gutierrez-Ibarluzea, Inaki; Benguria-Arrate, Gaizka [Basque Office for Health Technology Assessment, Vitoria-Gasteiz (ES); Keiding, Hans [University of Copenhagen, Department of Economics, Department of Economics, Copenhagen (DK); Mueller-Nordhorn, Jacqueline; Rieckmann, Nina [Charite - Universitaetsmedizin Berlin, Institute of Public Health, Berlin (DE); Walther, Mario; Schlattmann, Peter [Jena University Hospital, Friedrich Schiller University Jena, Institute of Medical Statistics, Computer Sciences and Documentation, Jena (DE); Collaboration: The DISCHARGE Trial Group

    2017-07-15

    More than 3.5 million invasive coronary angiographies (ICA) are performed in Europe annually. Approximately 2 million of these invasive procedures might be reduced by noninvasive tests because no coronary intervention is performed. Computed tomography (CT) is the most accurate noninvasive test for detection and exclusion of coronary artery disease (CAD). To investigate the comparative effectiveness of CT and ICA, we designed the European pragmatic multicentre DISCHARGE trial funded by the 7th Framework Programme of the European Union (EC-GA 603266). In this trial, patients with a low-to-intermediate pretest probability (10-60 %) of suspected CAD and a clinical indication for ICA because of stable chest pain will be randomised in a 1-to-1 ratio to CT or ICA. CT and ICA findings guide subsequent management decisions by the local heart teams according to current evidence and European guidelines. Major adverse cardiovascular events (MACE) defined as cardiovascular death, myocardial infarction and stroke as a composite endpoint will be the primary outcome measure. Secondary and other outcomes include cost-effectiveness, radiation exposure, health-related quality of life (HRQoL), socioeconomic status, lifestyle, adverse events related to CT/ICA, and gender differences. The DISCHARGE trial will assess the comparative effectiveness of CT and ICA. (orig.)

  16. Coronary computed tomography angiography for the assessment of chest pain: current status and future directions.

    Science.gov (United States)

    Nasis, Arthur; Meredith, Ian T; Cameron, James D; Seneviratne, Sujith K

    2015-12-01

    Chest pain is one of the most common presenting symptoms leading to presentation to medical clinics and Emergency Departments worldwide. Defining the nature and etiology of chest pain can pose a diagnostic dilemma for clinicians, despite the availability of several diagnostic algorithms and guidelines to assist them in evaluating these patients. Most investigations in patients with acute chest pain are initially performed to either exclude or diagnose and manage potentially life-threatening conditions such as acute coronary syndrome, pulmonary embolism and aortic dissection. In cases of stable chest pain syndromes, the focus shifts to determining the presence, extent and severity of coronary artery disease. In recent years, coronary computed tomography angiography (CCTA) is being increasingly used worldwide in the assessment of both stable and acute chest pain syndromes. This review evaluates the current evidence regarding the clinical utility of CCTA in the stable and acute chest pain settings and outlines the latest advances in CCTA techniques, including functional assessment of coronary stenoses, and their potential clinical application to improve patient care in a cost-effective manner.

  17. Stereoscopic vascular models of the head and neck: A computed tomography angiography visualization.

    Science.gov (United States)

    Cui, Dongmei; Lynch, James C; Smith, Andrew D; Wilson, Timothy D; Lehman, Michael N

    2016-01-01

    Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching anatomy includes use of computed tomography angiography (CTA) images of the head and neck to create clinically relevant 3D stereoscopic virtual models. These high resolution images of the arteries can be used in unique and innovative ways to create 3D virtual models of the vasculature as a tool for teaching anatomy. Blood vessel 3D models are presented stereoscopically in a virtual reality environment, can be rotated 360° in all axes, and magnified according to need. In addition, flexible views of internal structures are possible. Images are displayed in a stereoscopic mode, and students view images in a small theater-like classroom while wearing polarized 3D glasses. Reconstructed 3D models enable students to visualize vascular structures with clinically relevant anatomical variations in the head and neck and appreciate spatial relationships among the blood vessels, the skull and the skin. © 2015 American Association of Anatomists.

  18. Recurrence of Takotsubo Cardiomyopathy: Role of Multi- Detector Computed Tomography Coronary Angiography

    Directory of Open Access Journals (Sweden)

    Yaser Jenab

    2015-10-01

    Full Text Available Takotsubo cardiomyopathy (TCM, also known as stress-induced cardiomyopathy, is a clinical syndrome of transient left ventricular (LV apical wall motion abnormality with relative preservation of the basal heart segments in the absence of any significant atherosclerosis. Recurrence of this condition is rare. We report a postmenopausal woman, who experienced two episodes of TCM within 4 months following emotional and physical stress. In the first episode, she was admitted due to severe dyspnea, accompanied by sudden-onset, prolonged, burning chest pain and palpitation. Transthoracic echocardiography revealed akinesia of the LV, with the exception of the basal regions. Coronary angiography demonstrated no significant coronary artery disease, and follow-up echocardiography showed normalization of the LV wall motion abnormalities. In the second episode, she experienced similar symptoms and echocardiography revealed similar changes. Multi-detector computed tomography revealed normal coronary arteries. After 9 days, she was discharged in good condition; and at 3 months’ follow- up, she was symptom-free with normal echocardiography.

  19. Computed Tomography Angiography with a 192-slice Dual-source Computed Tomography System: Improvements in Image Quality and Radiation Dose

    Directory of Open Access Journals (Sweden)

    Philip V M Linsen

    2016-01-01

    Full Text Available Purpose: This study aims to compare image quality, radiation dose, and the influence of the heart rate on image quality of high-pitch spiral coronary computed tomography angiography (CCTA using 128-slice (second generation dual-source CT (DSCT and a 192-slice DSCT (third generation scanner. Materials and Methods: Two consecutive cohorts of fifty patients underwent CCTA by high-pitch spiral scan mode using 128 or 192-slice DSCT. The 192-slice DSCT system has a more powerful roentgen tube (2 × 120 kW that allows CCTA acquisition at lower tube voltages, wider longitudinal coverage for faster table speed (732 m/s, and the use of iterative reconstruction. Objective image quality was measured as the signal-to-noise ratio (SNR and contrast-to-noise ratio (CNR. Subjective image quality was evaluated using a Likert scale. Results: While the effective dose was lower with 192-slice DSCT (1.2 ± 0.5 vs. 0.6 ± 0.3 mSv; P < 0.001, the SNR (18.9 ± 4.3 vs. 11.0 ± 2.9; P < 0.001 and CNR (23.5 ± 4.8 vs. 14.3 ± 4.1; P < 0.001 were superior to 128-slice DSCT. Although patients scanned with 192-slice DSCT had a faster heart rate (59 ± 7 vs. 56 ± 6; P = 0.045, subjective image quality was scored higher (4.2 ± 0.8 vs. 3.0 ± 0.7; P < 0.001 compared to 128-slice DSCT. Conclusions: High-pitch spiral CCTA by 192-slice DSCT provides better image quality, despite a higher average heart rate, at lower radiation doses compared to 128-slice DSCT.

  20. Assessment of radiation exposure on a dual-source computed tomography-scanner performing coronary computed tomography-angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kirchhoff, S., E-mail: sonja.kirchhoff@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Herzog, P., E-mail: peter.herzog@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Johnson, T., E-mail: Thorsten.johnson@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Boehm, H., E-mail: holger.boehm@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Nikolaou, K., E-mail: konstantin.nikolaou@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Reiser, M.F., E-mail: maximilian.reiser@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany); Becker, C.H., E-mail: christoph.becker@med.uni-muenchen.d [Institute of Clinical Radiology, University Hospital Munich - Grosshadern, Ludwig Maximilians-Universitaet Muenchen, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich (Germany)

    2010-06-15

    Objective: The radiation exposure of a dual-source-64-channel multi-detector-computed-tomography-scanner (Somatom-Defintion, Siemens, Germany) was assessed in a phantom-study performing coronary-CT-angiography (CTCA) in comparison to patients' data randomly selected from routine scanning. Methods: 240 CT-acquisitions of a computed tomography dose index (CTDI)-phantom (PTW, Freiburg, Germany) were performed using a synthetically generated Electrocardiography (ECG)-signal with variable heart rates (30-180 beats per minute (bpm)). 120 measurements were acquired using continuous tube-output; 120 measurements were performed using ECG-synchronized tube-modulation. The pulsing window was set at minimum duration at 65% of the cardiac cycle between 30 and 75 bpm. From 90-180 bpm the pulsing window was set at 30-70% of the cardiac cycle. Automated pitch adaptation was always used. A comparison between phantom CTDI and two patient groups' CTDI corresponding to the two pulsing groups was performed. Results: Without ECG-tube-modulation CDTI-values were affected by heart-rate-changes resulting in 85.7 mGray (mGy) at 30 and 45 bpm, 65.5 mGy/60 bpm, 54.7 mGy/75 bpm, 46.5 mGy/90 bpm, 34.2 mGy/120 bpm, 27.0 mGy/150 bpm and 22.1 mGy/180 bpm equal to effective doses between 14.5 mSievert (mSv) at 30/45 bpm and 3.6 mSv at 180 bpm. Using ECG-tube-modulation these CTDI-values resulted: 32.6 mGy/30 bpm, 36.6 mGy/45 bpm, 31.4 mGy/60 bpm, 26.8 mGy/75 bpm, 23.7 mGy/90 bpm, 19.4 mGy/120 bpm, 17.2 mGy/150 bpm and 15.6 mGy/180 bpm equal to effective doses between 5.5 mSv at 30 bpm and 2.6 mSv at 180 bpm. Significant CTDI-differences were found between patients with lower/moderate and higher heart rates in comparison to the phantom CTDI-results. Conclusions: Dual source CTCA is particularly dose efficient at high heart rates when automated pitch adaptation, especially in combination with ECG-based tube-modulation is used. However in clinical routine scanning for patients with higher

  1. Retroaortic Left Renal Vein: Multidetector Computed Tomography Angiography Findings and Its Clinical Importance

    Energy Technology Data Exchange (ETDEWEB)

    Karaman, B.; Koplay, M.; Oezturk, E.; Basekim, C.C.; Ogul, H.; Mutlu, H.; Kizilkaya, E.; Kantarci, M. [Dept. of Radiology, Sivas Military Hospital, Sivas (Turkey)

    2007-04-15

    Purpose: To evaluate the appearance, type, frequency, and clinical importance of retroaortic left renal vein (RLRV) in patients examined with multidetector computed tomography (MDCT) angiography. Material and Methods: A total of 1856 patients who underwent CT with urological symptoms (hematuria, flank and abdominal pain, left gonadal vein varicocele) (n = 889) or with symptoms other than urological ones (n = 967) were prospectively evaluated for the presence of RLRV. CT was performed with 110 ml of iodinated contrast material through the antecubital vein at a rate of 3.5 ml/s. Late arterial and early venous phase volumetric data sets were acquired at 30 and 65 s, respectively, from the start of the intravenous injection of contrast medium. In addition to axial images, multiplanar reconstructions (MPR), maximum-intensity projection (MIP), and three-dimensional volume-rendering (3D VR) images were used to assess left renal vein anomalies. Left renal vein anomalies were classified into four types according to their appearance: I) RLRV joining the inferior vena cava (IVC) in the orthotopic position; II) RLRV joining the IVC at level L4-L5; III) circumaortic or collar left renal vein; IV) RLRV joining the left common iliac vein. Results: RLRV was detected in 68 (3.6%) of the 1856 patients, with 26, 22, 17, and three of types I, II, III, and IV, respectively. Forty-four of the 68 patients with RLRV (65%) were in the group with urological symptoms, while 24 patients (35%) were in the group without urological symptoms. Compression of the RLRV was found in 16 patients in the urological symptoms group, while compression was detected in only three patients in the other group. This difference was statistically significant (P<0.05). The most common urological symptom was hematuria. The frequency of urological symptoms was higher in groups II and IV compared to the other groups. Conclusion: MDCT angiography with axial, MPR, MIP, and 3D VR images is effective in the detection of

  2. Functional Testing or Coronary Computed Tomography Angiography in Patients With Stable Coronary Artery Disease.

    Science.gov (United States)

    Jørgensen, Mads E; Andersson, Charlotte; Nørgaard, Bjarne L; Abdulla, Jawdat; Shreibati, Jacqueline B; Torp-Pedersen, Christian; Gislason, Gunnar H; Shaw, Richard E; Hlatky, Mark A

    2017-04-11

    The choice of either anatomical or functional noninvasive testing to evaluate suspected coronary artery disease might affect subsequent clinical management and outcomes. This study analyzed the association of initial noninvasive cardiac testing in outpatients with stable symptoms, with subsequent use of medications, invasive procedures, and clinical outcomes. We studied patients enrolled in a Danish nationwide register who underwent initial noninvasive cardiac testing with either coronary computed tomography angiography (CTA) or functional testing (exercise electrocardiography or nuclear stress testing) from 2009 to 2015. Further use of noninvasive testing, invasive procedures, medications, and medical costs within 120 days were evaluated. Risks of long-term mortality and myocardial infarction (MI) were analyzed using adjusted Cox proportional hazard models. A total of 86,705 patients underwent either functional testing (n = 53,744, mean age 57.4 years, 49% males) or coronary CTA (n = 32,961, mean age 57.4 years, 45% males), and were followed for a median of 3.6 years. Compared with functional testing, there was significantly higher use of statins (15.9% vs. 9.1%), aspirin (12.7% vs. 8.5%), invasive coronary angiography (14.7% vs. 10.1%), and percutaneous coronary intervention (3.8% vs. 2.1%); all p testing, invasive procedures, and medications were higher after coronary CTA ($995 vs. $718; p mortality (2.1% vs. 4.0%) and MI hospitalization (0.8% vs. 1.5%) were lower after coronary CTA than functional testing (both p mortality (hazard ratio: 0.96; 95% confidence interval: 0.88 to 1.05), and a lower risk of MI (hazard ratio: 0.71; 95% confidence interval: 0.61 to 0.82). In stable patients undergoing initial evaluation for suspected coronary artery disease, coronary CTA was associated with greater use of statins, aspirin, and invasive procedures, and higher costs than functional testing. Coronary CTA was associated with a lower risk of MI, but a similar risk

  3. Characterizing analogue caldera collapse with computerized X-ray micro-tomography

    Science.gov (United States)

    Poppe, Sam; Holohan, Eoghan; Boone, Matthieu; Pauwels, Elin; Cnudde, Veerle; Kervyn, Matthieu

    2013-04-01

    Analogue models in the past mainly explored caldera collapse structures by documenting 2D model cross-sections. Kinematic aspects and 3D structures of caldera collapse are less well understood, although they are essential to interpret recent field and monitoring data. We applied high resolution radiography and computerized X-ray micro-tomography (µCT) to image the deformation during analogue fluid withdrawal in small-scale caldera collapse models. The models test and highlight the possibilities and limitations of µCT-scanning to qualitatively image and quantitatively analyse deformation of analogue volcano-tectonic experiments. High resolution interval radiography sequences document '2.5D' surface and internal model geometry, and subsidence kinematics of a collapsing caldera block into an emptying fluid body in an unprecedented way. During the whole drainage process, all subsidence was bound by caldera ring faults. Subsidence was associated with dilatation of the analogue granular material within the collapsing column. The temporal subsidence rate pattern within the subsiding volume comprised three phases: 1) Upward ring fault propagation, 2) Rapid subsidence with the highest subsidence rates within the uppermost subsiding volume, 3) Relatively slower subsidence rates over the whole column with intermittent subsidence rate acceleration. Such acceleration did almost never affect the whole column. By using radiography sequences it is possible in a non-destructive manner to obtain a continuous observation of fault propagation, down sag mechanisms and the subsequent development of collapse structures. Multi-angle µCT scans of the collapse result allow for a full virtual 3D reconstruction of the model. This leads to an unprecedented 3D view on fault geometries. The developed method is a step towards the quantitative documentation of volcano-tectonic models that would render data interpretations immediately comparable to monitoring data available from recent

  4. Morphometric analysis of the cervical spine of Indian population by using computerized tomography

    Directory of Open Access Journals (Sweden)

    Partha Sarathi Banerjee

    2012-08-01

    Full Text Available The purpose of the present study was to measure the surgically important morphological parameters of cervical spine region of a representative sample of Indian population from the images obtained through computerized tomography (CT. Another purpose has been to compare the computed statistical mean, standard deviation and range of variation of these data with those of other Asian population and also European/American populations. With that aim, ninety five (95 CT scan data of Indian people (73 for male patients and 22 for female patients pertaining to undeformed normal cervical spine has been collected from an Indian hospital. From these, 15 important morphological parameters have been measured. These values have been tabulated and their mean, standard deviation and range of variation have been computed. It has been found that pedicle dimensions of Indian people are smaller at almost all vertebra levels as compared to Caucasian people. Pedicle axis length for Indian people are found to be smaller at C3, C4 and C5 levels than those for other Asian people including Chinese people, but it is bigger at C6 and C7 levels. Indian people have longer measurements of pedicle length + lateral mass on an average than their other Asian counterparts at C5, C6 and C7 levels, but shorter measurements at C3 and C4 levels. The results of the present work may help in better understanding of morphological parameters of cervical spine region of Indian population. It may be further useful in designing spinal implants which would be biomechanically compatible to the anatomy of Indian people.

  5. Is computerized tomography useful in identifying abdominal catastrophes in patients presenting with peritonitis?

    Science.gov (United States)

    Yehia, Maha; de Zoysa, Janak R; Collins, John F

    2008-01-01

    Peritonitis is a significant source of morbidity and mortality in patients on peritoneal dialysis (PD). Symptoms may persist, requiring an emergency laparotomy. Although increasingly used, we find that, in PD patients, abdominal computerized tomography (CT) is ineffective in determining significant pathology. This study was undertaken to assess the diagnostic utility of CT for the identification of intra-abdominal collections in PD patients presenting with peritonitis. A retrospective chart review was undertaken of all patients that underwent abdominal CT scanning in the context of severe PD peritonitis in the past 2 years. All of these patients had at least one CT scan preoperatively. 133 patients presented with PD peritonitis; 19 patients had a contrast CT procedure (12 females, 7 males). Average age was 59.2 years; mean duration on PD was 43.8 months. 13 of 19 patients had gram-negative bacillary peritonitis, 6 of whom had polymicrobial peritonitis; 4 patients had fungal peritonitis and 2 had Staphylococcus aureus peritonitis. 26 CT scans were done in 19 patients an average of 10 days after presentation. 21 of 26 scans revealed no collections of surgical interest. 12 laparotomies were performed, with an average delay of 10.4 days from presentation to laparotomy. Of the 12 laparotomies, 6 found a drainable collection not seen on CT. Seven of the 19 patients died (37%) and no patient was able to return to PD. PD patients requiring emergency laparotomy following PD peritonitis have a high mortality rate. A negative abdominal CT in the setting of ongoing symptoms should not be taken as reassuring, nor should it delay proceeding to emergency laparotomy.

  6. A computerized tomography study of the morphological interrelationship between the temporal bones and the craniofacial complex

    Science.gov (United States)

    Costa, Helder Nunes; Slavicek, Rudolf; Sato, Sadao

    2012-01-01

    The hypothesis that the temporal bones are at the center of the dynamics of the craniofacial complex, directly influencing facial morphology, has been put forward long ago. This study examines the role of the spatial positioning of temporal bones (frontal and sagittal inclination) in terms of influencing overall facial morphology. Several 3D linear, angular and orthogonal measurements obtained through computerized analysis of virtual models of 163 modern human skulls reconstructed from cone-beam computed tomography images were analyzed and correlated. Additionally, the sample was divided into two subgroups based on the median value of temporal bone sagittal inclination [anterior rotation group (n = 82); posterior rotation group (n = 81)], and differences between groups evaluated. Correlation coefficients showed that sagittal inclination of the temporal bone was significantly (P < 0.01) related to midline flexion, transversal width and anterior–posterior length of the basicranium, to the anterior–posterior positioning of the mandible and maxilla, and posterior midfacial height. Frontal inclination of the temporal bone was significantly related (P < 0.01) to basicranium anterior–posterior and transversal dimensions, and to posterior midfacial height. In comparison with the posterior rotation group, the anterior rotation group presented a less flexed and anterior–posteriorly longer cranial base, a narrower skull, porion and the articular eminence located more superiorly and posteriorly, a shorter posterior midfacial height, the palatal plane rotated clockwise, a more retrognathic maxilla and mandible, and the upper posterior occlusal plane more inclined and posteriorly located. The results suggest that differences in craniofacial morphology are highly integrated with differences in the positional relationship of the temporal bones. The sagittal inclination of the temporal bone seems to have a greater impact on the 3D morphology of the craniofacial complex than

  7. New onset seizures: Etiology and co-relation of clinical features with computerized tomography and electroencephalography

    Directory of Open Access Journals (Sweden)

    V Muralidhar

    2015-01-01

    Full Text Available Aims and Objective: To establish whether the reported episode was a seizure, to determine the cause of seizure by identifying the risk factors, lab, radiological and electroencephalography (EEG evaluation to determine any underlying structural abnormality and to decide whether anti-epileptics therapy is essential. Settings and Design: This was a descriptive study. Materials and Methods: (1 Source of data - All the patients with inclusion criteria attending to the medicine outpatient department (OPD/wards. Sample size = 50 cases. (2 Study subjects - Inclusion criteria: All patients >15 years age group presenting in medicine OPD/wards with the first episode of seizure. Exclusion criteria: Seizures on treatment and head injury. Methods of Collection of Data: Each patient was subjected to the detailed evaluation including history, precipitating factors, and symptomatology recorded accordingly. History of hypertension, diabetes mellitus, tuberculosis (TB was enquired into. Family history of epilepsy, TB was recorded. Complete clinical evaluation and thorough investigations-complete blood count, urine examination, blood urea nitrogen, random blood sugar, chest X-ray, computerized tomography (CT scan and EEG were done for all patients in the inclusion criteria. Anti-epileptics were started if either CT/EEG was abnormal, rest of the patients were not given anti-epileptics. Follow-up was done for 6 months, and any recurrence of seizures was noted. The data collected from cases in the inclusion criteria were recorded in a Master chart. Data analysis was done using appropriate statistical tests and graphs. Results and Conclusions: Peak incidence of new onset seizure was second to third decade (25 cases; 50%, max cases <25 years, male: Female ratio of 2.12:1, duration of seizure <5 min (30 cases; 60%, evidence of TB = 6 cases (12%, alcohol intake = 5 cases (10%, developmental delay = 3 cases (6%, family history = 3 cases (6%, old cerebro-vascular accident

  8. Computerized tomography attenuation values can be used to differentiate hydronephrosis from pyonephrosis.

    Science.gov (United States)

    Yuruk, Emrah; Tuken, Murat; Sulejman, Suhejb; Colakerol, Aykut; Serefoglu, Ege Can; Sarica, Kemal; Muslumanoglu, Ahmet Yaser

    2017-03-01

    To determine the diagnostic value of computerized tomography (CT) in differentiating pyonephrosis from hydronephrosis on the basis of attenuation values (Hounsfield unit-HU). Data of the patients with grades 1-3 hydronephrosis on abdominopelvic CT, who underwent nephrostomy tube placement for decompression of the collecting system, were retrospectively analyzed. Patient demographics and CT findings were recorded along with the first access urine culture results. Three physicians calculated the surface areas and the attenuation values of the dilated collecting systems using the system software. Mean HU of pyonephrosis and hydronephrosis cases was compared. A total of 105 patients with the mean age of 47.7 ± 15.5 (range 20-80) were included. The interclass correlation coefficient of three physicians was 0.981 for HU measurement and 0.999 for calculation of collecting system surface area. Of the patients, 47 (44.8 %) had pyonephrosis. Mean surface areas of the collecting system were similar in patients with pyonephrosis and hydronephrosis (1481.13 ± 1562.94 vs. 1612.94 ± 2261.4 mm2, p = 0.735). Urine cultures were positive in all patients with pyonephrosis, whereas 12.7 % of hydronephrosis cases had bacterial in first access urine culture. The HU of the patients with pyonephrosis was significantly higher that that of patients with hydronephrosis (13.51 ± 13.29 vs. 4.67 ± 5.37, p = 0.0001). Having a HU of 9.21 or over diagnosed pyonephrosis accurately with 65.96 % sensitivity and 87.93 % specificity. Measuring attenuation values of the collecting system may be useful to differentiate pyonephrosis from hydronephrosis. Diagnosing pyonephrosis accurately may avoid septic complications.

  9. Right arm injection of contrast medium reduces venous artifacts in head and neck multislice spiral computed tomography angiography.

    Science.gov (United States)

    Fang, H; Song, Y-L; Li, X-S; Bi, Y-M; Wang, P; Fan, H-X; Meng, L M; Hu, H-X

    2015-12-01

    We tested whether injection of contrast medium via right or left arm would affect venous artifacts on head and neck multislice spiral computed tomography (CT) angiography. 326 patients were enrolled. Each patient was injected with 10 ml of contrast medium at 5 ml/sec. Time of peak contrast value plus an additional 1 sec was defined as delay time. Another 40 ml of contrast medium were injected with the same injection speed. The scanning area ranged from the aortic arch to the top of the head. Left and right forearms were used for intravenous injections of contrast medium in, respectively, 151 and 175 patients. Comparative analyses of image quality included determining contrast medium residues remaining in the superior vena cava, brachiocephalic vein, or subclavian vein, and comparisons of quality of three-dimensional CT angiography. In 75% of head and neck angiographies, the delay time of the common carotid artery ranged from 16 to 22 sec. In 60% of the images, the quality was graded as excellent, with the left arm injection resulting in delay time of > 23 sec and the right arm delay time of > 18 sec. The CT imaging quality after contrast injections via left or right arms was statistically significant (p arm injection was better than after left arm injection. Intravenous injection of contrast medium via right arm reduces artifacts from contrast medium residues and improves the image quality of head and neck CT angiography.

  10. Identifying the Adamkiewicz artery using 3-T time-resolved magnetic resonance angiography: its role in addition to multidetector computed tomography angiography.

    Science.gov (United States)

    Takagi, Hidenobu; Ota, Hideki; Natsuaki, Yutaka; Komori, Yoshiaki; Ito, Koki; Saiki, Yoshikatsu; Takase, Kei

    2015-12-01

    This study assessed Adamkiewicz artery (AKA) detectability using multidetector computed tomography angiography (MDCTA) and time-resolved magnetic resonance angiography (MRA) at 3 T. This Institutional Review Board-approved retrospective study included 117 patients with thoracoabdominal aortic disease scheduled for aortic repair. A total of 111 patients underwent MDCTA for AKA identification; 43 patients whose AKA identification was not definitive on MDCTA underwent additional MRA. The remaining six patients, who were not indicated for iodine-contrast MDCTA, underwent only MRA. Two reviewers independently evaluated both MDCTA and MRA data. The 4-point confidence index was used. Grades 3-4 were considered sufficient for AKA diagnosis. AKA detectability was at 80.2% (89/111) using MDCTA and 89.8% (44/49) with MRA. In the 43 patients who underwent both MDTCA and MRA, the AKA detectability and consensus grades were significantly elevated using MRA vs. MDCTA (detectability: 88.4 vs. 69.8%, respectively, p = 0.043). AKA detectability was also higher in aortic aneurysm than aortic dissection patients on MDCTA (90.9 vs. 69.6%, respectively, p < 0.01), but not on MRA (92.9 vs. 88.6%, respectively, p = 0.99). Time-resolved MRA at 3 T increases AKA detectability and is recommended for patients without definitive AKA identification on MDCTA.

  11. MR angiography with parallel acquisition for assessment of the visceral arteries: comparison with conventional MR angiography and 64-detector-row computed tomography

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    Sutter, Reto [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Heilmaier, Christina [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Lutz, Amelie M.; Willmann, Juergen K. [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States); Weishaupt, Dominik [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Hospital Triemli, Department of Radiology, Zurich (Switzerland); Seifert, Burkhardt [University of Zurich, Biostatistics Unit, Institute of Social and Preventive Medicine, Zurich (Switzerland)

    2009-11-15

    The purpose of the study was to retrospectively compare three-dimensional gadolinium-enhanced magnetic resonance angiography (conventional MRA) with MRA accelerated by a parallel acquisition technique (fast MRA) for the assessment of visceral arteries, using 64-detector-row computed tomography angiography (MDCTA) as the reference standard. Eighteen patients underwent fast MRA (imaging time 17 s), conventional MRA (29 s) and MDCTA of the abdomen and pelvis. Two independent readers assessed subjective image quality and the presence of arterial stenosis. Data were analysed on per-patient and per-segment bases. Fast MRA yielded better subjective image quality in all segments compared with conventional MRA (P = 0.012 for reader 1, P = 0.055 for reader 2) because of fewer motion-induced artefacts. Sensitivity and specificity of fast MRA for the detection of arterial stenosis were 100% for both readers. Sensitivity of conventional MRA was 89% for both readers, and specificity was 100% (reader 1) and 99% (reader 2). Differences in sensitivity between the two types of MRA were not significant for either reader. Interobserver agreement for the detection of arterial stenosis was excellent for fast ({kappa} = 1.00) and good for conventional MRA ({kappa} = 0.76). Thus, subjective image quality of visceral arteries remains good on fast MRA compared with conventional MRA, and the two techniques do not differ substantially in the grading of arterial stenosis, despite the markedly reduced acquisition time of fast MRA. (orig.)

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

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    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.

  13. Swept Source Optical Coherence Tomography Angiography for Contact Lens-Related Corneal Vascularization

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    Marcus Ang

    2016-01-01

    Full Text Available Purpose. To describe a novel technique of adapting a swept-source optical coherence tomography angiography (OCTA to image corneal vascularization. Methods. In this pilot cross-sectional study, we obtained 3 × 3 mm scans, where 100,000 A-scans are acquired per second with optical axial resolution of 8 μm and lateral resolution of 20 μm. This was performed with manual “XYZ” focus without the anterior segment lens, until the focus of the corneoscleral surface was clearly seen and the vessels of interest were in focus on the corresponding red-free image. En face scans were evaluated based on image quality score and repeatability. Results. We analyzed scans from 10 eyes (10 patients with corneal vascularization secondary to contact lens use in 4 quadrants, with substantial repeatability of scans in all quadrants (mean image quality score 2.7 ± 0.7; κ=0.75. There was no significant difference in image quality scores comparing quadrants (superior temporal: 2.9 ± 0.6, superior nasal: 2.8 ± 0.4, inferior temporal: 2.5 ± 0.9, and inferior nasal: 2.4 ± 1.0; P=0.276 and able to differentiate deep and superficial corneal vascularization. Conclusion. This early clinical study suggests that the swept-source OCTA used may be useful for examining corneal vascularization, which may have potential for clinical applications such as detecting early limbal stem cell damage.

  14. GPU accelerated optical coherence tomography angiography using strip-based registration (Conference Presentation)

    Science.gov (United States)

    Heisler, Morgan; Lee, Sieun; Mammo, Zaid; Jian, Yifan; Ju, Myeong Jin; Miao, Dongkai; Raposo, Eric; Wahl, Daniel J.; Merkur, Andrew; Navajas, Eduardo; Balaratnasingam, Chandrakumar; Beg, Mirza Faisal; Sarunic, Marinko V.

    2017-02-01

    High quality visualization of the retinal microvasculature can improve our understanding of the onset and development of retinal vascular diseases, which are a major cause of visual morbidity and are increasing in prevalence. Optical Coherence Tomography Angiography (OCT-A) images are acquired over multiple seconds and are particularly susceptible to motion artifacts, which are more prevalent when imaging patients with pathology whose ability to fixate is limited. The acquisition of multiple OCT-A images sequentially can be performed for the purpose of removing motion artifact and increasing the contrast of the vascular network through averaging. Due to the motion artifacts, a robust registration pipeline is needed before feature preserving image averaging can be performed. In this report, we present a novel method for a GPU-accelerated pipeline for acquisition, processing, segmentation, and registration of multiple, sequentially acquired OCT-A images to correct for the motion artifacts in individual images for the purpose of averaging. High performance computing, blending CPU and GPU, was introduced to accelerate processing in order to provide high quality visualization of the retinal microvasculature and to enable a more accurate quantitative analysis in a clinically useful time frame. Specifically, image discontinuities caused by rapid micro-saccadic movements and image warping due to smoother reflex movements were corrected by strip-wise affine registration estimated using Scale Invariant Feature Transform (SIFT) keypoints and subsequent local similarity-based non-rigid registration. These techniques improve the image quality, increasing the value for clinical diagnosis and increasing the range of patients for whom high quality OCT-A images can be acquired.

  15. Configurations of the circle of Willis: a computed tomography angiography based study on a Polish population.

    Science.gov (United States)

    Klimek-Piotrowska, W; Kopeć, M; Kochana, M; Krzyżewski, R M; Tomaszewski, K A; Brzegowy, P; Walocha, J

    2013-11-01

    The aim of the study was to investigate the distribution of the circle of Willis variants in Polish population by means of computed tomography angiography (CTA). The results were then analysed and compared with another study that used similar methods but that was carried out on an ethnically distinct population. Patients presenting with intracranial pathology were excluded from the initial study population. In total, 250 CTA belonging to 129 female and 121 male patients were reviewed. A modified classification system of the circle was proposed, which took into consideration the anterior and the posterior aspects of the circle individually. The typical variant of Willis's circle occurred in 16.80% of cases. The anterior and the posterior portions of the circle were normal in 47.20% and 26.80% of the patients respectively. As for the anterior part, lack of the anterior communicating artery was the most frequent abnormality (22.80%). Bilateral absence of posterior communicating arteries was the most common anomaly in the posterior part of the circle (29.20%). This type of anomaly was also the most common, when taking into consideration the entire circle (12.00%). There were statistically significant differences between the age groups and genders when considering the occurrence of an incomplete circle. Overall, a substantial proportion of patients manifested clinically important variants that were incapable of providing collateral circulation. Comparison with other imaging-based and cadaveric studies revealed noticeable differences, that may have resulted from the variable technical features of other studies or other factors such as the ethnical origins of the studied populations.

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

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    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.

  17. "Pulmonary Vein Sign" for Pulmonary Embolism Diagnosis in Computed Tomography Angiography.

    Science.gov (United States)

    Souza, Luciana Volpon Soares; Zanon, Matheus; Souza, Arthur Soares; Irion, Klaus; Penha, Diana; Alves, Giordano Rafael Tronco; Marchiori, Edson; Hochhegger, Bruno

    2017-12-01

    Considering that pulmonary arterial obstruction decreases venous flow, we hypothesized that filling defects in pulmonary veins can be identified in areas adjacent to pulmonary embolism (PE). This sign was named the "pulmonary vein sign" (PVS), and we evaluated its prevalence and performance for PE diagnosis in computed tomography pulmonary angiography (CTPA). This retrospective study enrolled consecutive patients with clinical suspicion of PE who underwent CTPA scan. The PVS was defined by the following criteria: (a) presence of a homogeneous filling defect of at least 2 cm in a pulmonary vein; (b) attenuation of the left atrium > 160 Hounsfield units. Using the cases that presented PE on CTPA as reference, sensitivity, specificity, and positive and negative predictive values were calculated for PVS. In total, 119 patients (73 female; mean age, 62 years) were included in this study. PE was diagnosed in 44 (35.8%) patients. The PVS was present in 16 out of 44 patients with PE. Sensitivity was 36.36% (95% confidence interval (CI) 22.83-52.26%); specificity, 98.67% (95% CI 91.79-99.93%); positive predictive value, 94.12% (95% CI 69.24-99.69%); negative predictive value, 72.55% (95% CI 62.67-80.70%). The Kappa index for the PVS was good (0.801; 95% CI 0.645-0.957). PVS was correlated with lobar and segmental pulmonary embolism (p < 0.01). Despite a low sensitivity, presence of the pulmonary vein sign was highly specific for PE, with a good agreement between readers. This sign could contribute for PE diagnosis on CTPA studies.

  18. Incidental Findings in Patients Evaluated for Pulmonary Embolism Using Computed Tomography Angiography

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    Masoud Pezeshki Rad

    2014-05-01

    Full Text Available Introduction: Pulmonary embolism (PE is a common lethal disease that its clinical symptoms may be seen in many other diseases. Computed tomography pulmonary angiography (CTPA is a valuable diagnostic modality for detection of PE. In addition, it can accurately detect the other diseases with clinical symptoms similar to PE. The aim of this study is to evaluate the frequency of PE and nonembolic disease with similar clinical symptoms including pulmonary, pleural, mediastinal, and cardiovascular diseases that have been detected by CTPA and to describe the importance of reporting these CT findings. Materials and Methods: In this cross‐sectional study, we evaluated the medical records of CTPA in 300 patients of suspected PE between March 2012 and February 2013 in Imam Reza Hospital and Ghaem Hospital in Mashhad University of Medical Sciences, Mashhad, Iran. Demographic information and the results of CTPA of these patients were re‐evaluated. One radiologist reviewed all of the CTPA and the results have been analyzed by SPSS‐16 software. Results: In this study, PE was detected in 18.7% of patients. Multiple incidental imaging findings were diagnosed as follow: pulmonary consolidation (33.2%, pleural effusion (48.7%, pulmonary nodules (10%, pulmonary masses (1.3%, pneumothorax (4.7%, mediastinal mass and lymphadenopathy (9.3%, aortic calcification (42%, coronary arteries calcification (27.3%, mitral valve calcification (2 %, cardiomegaly (30.7%, and the evidences of right ventricular dysfunction (6.7%. Conclusion: A group of disease can cause the clinical symptoms similar to that of PE. Among them, pulmonary consolidation and pleural effusion have much higher frequency than PE. In addition, CTPA can show pathologic findings in the patients that need follow‐up. It is important to detect and report these imaging findings because some of them may change the treatment and prognosis of patient who are suspected to have PE.

  19. Run-Off Computed Tomography Angiography (CTA for Discriminating the Underlying Causes of Intermittent Claudication.

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    Alexandra Preuß

    Full Text Available To evaluate run-off computed tomography angiography (CTA of abdominal aorta and lower extremities for detecting musculoskeletal pathologies and clinically relevant extravascular incidental findings in patients with intermittent claudication (IC and suspected peripheral arterial disease (PAD. Does run-off CTA allow image-based therapeutic decision making by discriminating the causes of intermittent claudication in patients with suspected peripheral arterial disease PAD?Retrospective re-evaluation of CTAs performed in patients with acute or chronic intermittent claudication (i.e., Fontaine stages I to IIB between January 2005 and October 2013. Allocation to one of three categories of underlying causes of IC symptoms: vascular, musculoskeletal (MSK or both. Clinically relevant extravascular incidental findings were evaluated. Medical records were reviewed to verify specific therapies as well as main and incidental findings.While focused on vascular imaging, CTA image quality was sufficient for evaluation of the MSK system in all cases. The underlying cause of IC was diagnosed in run-off CTA as vascular, MSK and a combination in n = 138 (65%, n = 10 (4%, and n = 66 (31% cases, respectively. Specific vascular or MSK therapy was recorded in n = 123 and n = 9 cases. In n = 82, no follow-up was possible. Clinically relevant extravascular incidental findings were detected in n = 65 patients (30% with neoplasia, ascites and pleural effusion being the most common findings.Run-off CTA allows identification of vascular, MSK, and combined causes of IC in patients with suspected PAD and can guide specific therapy. CTA also allowed confident detection of crEVIF although detection did not necessarily trigger workup or treatment.

  20. Impact of Multiple En Face Image Averaging on Quantitative Assessment from Optical Coherence Tomography Angiography Images.

    Science.gov (United States)

    Uji, Akihito; Balasubramanian, Siva; Lei, Jianqin; Baghdasaryan, Elmira; Al-Sheikh, Mayss; Sadda, SriniVas R

    2017-07-01

    To investigate the impact of multiple en face image averaging on quantitative measurements of the retinal microvasculature using optical coherence tomography angiography (OCTA). Prospective, observational, cross-sectional case series. Twenty-one healthy individuals with normal eyes. Macular OCTA images were acquired from all participants using the Zeiss Cirrus 5000 with Angioplex OCTA software (Carl Zeiss Meditec, Dublin, CA). Nine OCTA cube scans per eye were obtained and 9 superficial retinal layer (SRL) and deep retinal layer (DRL) en face OCTA image slabs were averaged individually after registration. Quantitative parameters from the retinal microvasculature were measured on binarized and skeletonized OCTA images and compared with single OCTA images without averaging. Vessel density (VD), vessel length density (VLD), vessel diameter index (VDI), and fractal dimension (FD). Participants with artifact or poor image quality were excluded, leaving 18 eyes for the analysis. After averaging, qualitatively there was apparent reduction in background noise, and fragmented vessels in the images before averaging became continuous with smoother walls and showed sharper contrast in both the SRL and DRL. Binarized and skeletonized derivates of these averaged images also showed fewer line fragments and dots in nonvascular areas and more continuous vessel images than those of images without averaging. In both SRL and DRL, VD (P = 0.0010 and P = 0.0003, respectively), VLD (P images improves image quality and also significantly impacts quantitative measurements. Reducing noise that could be misinterpreted as flow and annealing discontinuous vessel segments seem to be major mechanisms by which averaging may be of benefit. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  1. Characteristic detected on computed tomography angiography predict coronary artery plaque progression in non-culprit lesions

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    Tan, Ya Hang; Zhou, Jia Zhou; Zhou, Ying; Yang, Xiaobo; Yang, Jun Jie; Chen, Yun Dai [Dept. of Cardiology, Chinese PLA General Hospital, Beijing (China)

    2017-06-15

    This study sought to determine whether variables detected on coronary computed tomography angiography (CCTA) would predict plaque progression in non-culprit lesions (NCL). In this single-center trial, we analyzed 103 consecutive patients who were undergoing CCTA and percutaneous coronary intervention (PCI) for culprit lesions. Follow-up CCTA was scheduled 12 months after the PCI, and all patients were followed for 3 years after their second CCTA examination. High-risk plaque features and epicardial adipose tissue (EAT) volume were assessed by CCTA. Each NCL stenosis grade was compared visually between two CCTA scans to detect plaque progression, and patients were stratified into two groups based on this. Logistic regression analysis was used to evaluate the factors that were independently associated with plaque progression in NCLs. Time-to-event curves were compared using the log-rank statistic. Overall, 34 of 103 patients exhibited NCL plaque progression (33%). Logistic regression analyses showed that the NCL progression was associated with a history of ST-elevated myocardial infarction (odds ratio [OR] = 5.855, 95% confidence interval [CI] = 1.391–24.635, p = 0.016), follow-up low-density lipoprotein cholesterol level (OR = 6.832, 95% CI = 2.103–22.200, p = 0.001), baseline low-attenuation plaque (OR = 7.311, 95% CI = 1.242–43.028, p = 0.028) and EAT (OR = 1.015, 95% CI = 1.000–1.029, p = 0.044). Following the second CCTA examination, major adverse cardiac events (MACEs) were observed in 12 patients, and NCL plaque progression was significantly associated with future MACEs (log rank p = 0.006). Noninvasive assessment of NCLs by CCTA has potential prognostic value.

  2. Quantification of aortic annulus in computed tomography angiography: Validation of a fully automatic methodology.

    Science.gov (United States)

    Gao, Xinpei; Boccalini, Sara; Kitslaar, Pieter H; Budde, Ricardo P J; Attrach, Mohamed; Tu, Shengxian; de Graaf, Michiel A; Ondrus, Tomas; Penicka, Martin; Scholte, Arthur J H A; Lelieveldt, Boudewijn P F; Dijkstra, Jouke; Reiber, Johan H C

    2017-08-01

    Automatic accurate measuring of the aortic annulus and determination of the optimal angulation of X-ray projection are important for the trans-catheter aortic valve replacement (TAVR) procedure. The objective of this study was to present a novel fully automatic methodology for the quantification of the aortic annulus in computed tomography angiography (CTA) images. CTA datasets of 26 patients were analyzed retrospectively with the proposed methodology, which consists of a knowledge-based segmentation of the aortic root and detection of the orientation and size of the aortic annulus. The accuracy of the methodology was determined by comparing the automatically derived results with the reference standard obtained by semi-automatic delineation of the aortic root and manual definition of the annulus plane. The difference between the automatic annulus diameter and the reference standard by observer 1 was 0.2±1.0mm, with an inter-observer variability of 1.2±0.6mm. The Pearson correlation coefficient for the diameter was good (0.92 for observer 1). For the first time, a fully automatic tool to assess the optimal projection curves was presented and validated. The mean difference between the optimal projection curves calculated based on the automatically defined annulus plane and the reference standard was 6.4° in the cranial/caudal (CRA/CAU) direction. The mean computation time was short with around 60s per dataset. The new fully automatic and fast methodology described in this manuscript not only provided precise measurements about the aortic annulus size with results comparable to experienced observers, but also predicted optimal X-ray projection curves from CTA images. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Radiation Maculopathy After Proton Beam Therapy for Uveal Melanoma: Optical Coherence Tomography Angiography Alterations Influencing Visual Acuity.

    Science.gov (United States)

    Matet, Alexandre; Daruich, Alejandra; Zografos, Leonidas

    2017-08-01

    To analyze microvascular and structural changes in radiation maculopathy and their influence on visual acuity (VA), using optical coherence tomography (OCT) and OCT angiography (OCTA). This was a retrospective analysis of consecutive patients with radiation maculopathy, 12 months or more after proton-beam irradiation for uveal melanoma, imaged with fluorescein angiography, OCT, and OCTA. Clinical parameters potentially affecting VA were recorded, including OCTA-derived metrics: foveal avascular zone (FAZ) area, vascular density, and local fractal dimension of the superficial (SCP) and deep capillary plexuses (DCP). Nonirradiated fellow eyes served as controls. Ninety-three patients were included. FAZ was larger, while SCP/DCP capillary density and local fractal dimension were lower in the 35 irradiated than in the 35 fellow eyes (P maculopathy is influenced by structural and microvascular factors identified with OCTA, including FAZ area and DCP integrity.

  4. Deep Retinal Layer Microvasculature Dropout Detected by the Optical Coherence Tomography Angiography in Glaucoma.

    Science.gov (United States)

    Suh, Min Hee; Zangwill, Linda M; Manalastas, Patricia Isabel C; Belghith, Akram; Yarmohammadi, Adeleh; Medeiros, Felipe A; Diniz-Filho, Alberto; Saunders, Luke J; Weinreb, Robert N

    2016-12-01

    To investigate factors associated with dropout of the parapapillary deep retinal layer microvasculature assessed by optical coherence tomography angiography (OCTA) in glaucomatous eyes. Cross-sectional study. Seventy-one eyes from 71 primary open-angle glaucoma (POAG) patients with β-zone parapapillary atrophy (βPPA) enrolled in the Diagnostic Innovations in Glaucoma Study. Parapapillary deep-layer microvasculature dropout was defined as a complete loss of the microvasculature located within the deep retinal layer of the βPPA from OCTA-derived optic nerve head vessel density maps by standardized qualitative assessment. Circumpapillary vessel density (cpVD) within the retinal nerve fiber layer (RNFL) also was calculated using OCTA. Choroidal thickness and presence of focal lamina cribrosa (LC) defects were determined using swept-source optical coherence tomography. Presence of parapapillary deep-layer microvasculature dropout. Parameters including age, systolic and diastolic blood pressure, axial length, intraocular pressure, disc hemorrhage, cpVD, visual field (VF) mean deviation (MD), focal LC defects βPPA area, and choroidal thickness were analyzed. Parapapillary deep-layer microvasculature dropout was detected in 37 POAG eyes (52.1%). Eyes with microvasculature dropout had a higher prevalence of LC defects (70.3% vs. 32.4%), lower cpVD (52.7% vs. 58.8%), worse VF MD (-9.06 dB vs. -3.83 dB), thinner total choroidal thickness (126.5 μm vs. 169.1 μm), longer axial length (24.7 mm vs. 24.0 mm), larger βPPA (1.2 mm2 vs. 0.76 mm2), and lower diastolic blood pressure (74.7 mmHg vs. 81.7 mmHg) than those without dropout (P microvasculature dropout in glaucomatous eyes. Longitudinal studies are required to elucidate the temporal relationship between parapapillary deep-layer microvasculature dropout and systemic and ocular factors. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  5. Reproducibility of Perfusion Parameters of Optic Disc and Macula in Rhesus Monkeys by Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Li, Jing; Yang, Yi-Quan; Yang, Di-Ya; Liu, Xiang-Xiang; Sun, Yun-Xiao; Wei, Shi-Fei; Wang, Ning-Li

    2016-05-05

    Optical coherence tomography (OCT) angiography is a novel technique by which we can detect the local perfusion of fundus directly. The aim of this study was to evaluate the reproducibility of optic disc and macular flow perfusion parameters in rhesus monkeys using OCT angiography. Eighteen healthy monkeys (18 eyes) were subjected to optic disc and macula flow index measurements via a high-speed and high-resolution spectral-domain OCT XR Avanti with a split-spectrum amplitude de-correlation angiography algorithm. Right eye was imaged 3 times during the first examination and once during each of the two following examinations. The intra-visit and inter-visit intraclass correlation coefficients (ICCs) were both determined. The average flow indices of the four optic disc area layers were 0.171 ± 0.009 (optic nerve head), 0.015 ± 0.004 (vitreous), 0.052 ± 0.009 (radial peripapillary capillary), and 0.167 ± 0.011 (choroid). Average flow indices of the four macula area layers were 0.044 ± 0.011 (superficial retina), 0.036 ± 0.011 (deep retina), 0.016 ± 0.009 (outer retina), and 0.155 ± 0.013 (choroid). Intra-visit (ICC value: 0.821-0.954) and inter-visit (ICC value: 0.844-0.899) repeatability were both high. The study is about the reproducibility of optic disc and macular perfusion parameters as measured by OCT angiography in healthy rhesus monkeys. Flow index measurement reproducibility is high for both the optic disc and macula of normal monkey eyes. OCT angiography might be a useful technique to assess changes when examining monkeys with experimental ocular diseases.

  6. Relationship Between Quantitative Adverse Plaque Features From Coronary Computed Tomography Angiography and Downstream Impaired Myocardial Flow Reserve by 13N-Ammonia Positron Emission Tomography: A Pilot Study.

    Science.gov (United States)

    Dey, Damini; Diaz Zamudio, Mariana; Schuhbaeck, Annika; Juarez Orozco, Luis Eduardo; Otaki, Yuka; Gransar, Heidi; Li, Debiao; Germano, Guido; Achenbach, Stephan; Berman, Daniel S; Meave, Aloha; Alexanderson, Erick; Slomka, Piotr J

    2015-10-01

    We investigated the relationship of quantitative plaque features from coronary computed tomography (CT) angiography and coronary vascular dysfunction by impaired myocardial flow reserve (MFR) by (13)N-Ammonia positron emission tomography (PET). Fifty-one patients (32 men, 62.4±9.5 years) underwent combined rest-stress (13)N-ammonia PET and CT angiography scans by hybrid PET/CT. Regional MFR was measured from PET. From CT angiography, 153 arteries were evaluated by semiautomated software, computing arterial noncalcified plaque (NCP), low-density NCP (NCPensemble machine-learning algorithm into a composite risk score to predict impaired MFR (MFR≤2.0) by PET in each artery. Nineteen patients had impaired regional MFR in at least 1 territory (41/153 vessels). Patients with impaired regional MFR had higher arterial NCP (32.4% versus 17.2%), low-density NCP (7% versus 4%), and total plaque burden (37% versus 19.3%, P<0.02). In multivariable analysis with 10-fold cross-validation, NCP burden was the most significant predictor of impaired MFR (odds ratio, 1.35; P=0.021 for all). For prediction of impaired MFR with 10-fold cross-validation, receiver operating characteristics area under the curve for the composite score was 0.83 (95% confidence interval, 0.79-0.91) greater than for quantitative stenosis (0.66, 95% confidence interval, 0.57-0.76, P=0.005). Compared with stenosis, arterial NCP burden and a composite score combining quantitative stenosis and plaque burden from CT angiography significantly improves identification of downstream regional vascular dysfunction. © 2015 American Heart Association, Inc.

  7. The accuracy of noncontrast spiral computerized tomography in detecting lucent renal stones: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Ayman Adwan

    2015-01-01

    Full Text Available Renal stones are one of the most common diseases in the urology field that are easily diagnosed by one of the standard imaging techniques. Noncontrast spiral computerized tomography (CT can detect up to 95% of the renal, ureteric and bladder stones, especially those with calcium composition, and considered nowadays one of the most accurate methods for detecting undetectable stones by other modalities. We report a case of a 60-year-old female who presented with colicky right flank pain due to large calcium oxalate renal stone that is undetected by standard imaging technique including spiral CT scan. Uretroscopy diagnosed and ultimately treat this patient problem.

  8. The accuracy of noncontrast spiral computerized tomography in detecting lucent renal stones: A case report and literature review.

    Science.gov (United States)

    Adwan, Ayman; Binsaleh, Saleh

    2015-01-01

    Renal stones are one of the most common diseases in the urology field that are easily diagnosed by one of the standard imaging techniques. Noncontrast spiral computerized tomography (CT) can detect up to 95% of the renal, ureteric and bladder stones, especially those with calcium composition, and considered nowadays one of the most accurate methods for detecting undetectable stones by other modalities. We report a case of a 60-year-old female who presented with colicky right flank pain due to large calcium oxalate renal stone that is undetected by standard imaging technique including spiral CT scan. Uretroscopy diagnosed and ultimately treat this patient problem.

  9. Serial measurement of regional cerebral blood flow in patients with SAH using 133Xe inhalation and emission computerized tomography

    DEFF Research Database (Denmark)

    Mickey, B; Vorstrup, S; Voldby, Bo

    1984-01-01

    defined regional flow decrease in the vascular territories of the anterior or middle cerebral arteries. Severe vasospasm was noted in three of these patients in whom arteriography was performed in the 2nd week post SAH. Diffuse bihemispheric CBF decreases were noted later in the course of delayed......A noninvasive three-dimensional method for measuring cerebral blood flow (CBF), xenon-133 inhalation and emission computerized tomography, was used to investigate the CBF changes accompanying delayed neurological deterioration following subarachnoid hemorrhage (SAH). A total of 67 measurements were...

  10. Calculating the number of shock waves, expulsion time, and optimum stone parameters based on noncontrast computerized tomography characteristics.

    Science.gov (United States)

    Foda, Khaled; Abdeldaeim, Hussein; Youssif, Mohamed; Assem, Akram

    2013-11-01

    To define the parameters that accompanied a successful extracorporeal shock wave lithotripsy (ESWL), namely the number of shock waves (SWs), expulsion time (ET), mean stone density (MSD), and the skin-to-stone distance (SSD). A total of 368 patients diagnosed with renal calculi using noncontrast computerized tomography had their MSD, diameter, and SSD recorded. All patients were treated using a Siemens lithotripter. ESWL success meant a stone-free status or presence of residual fragments 934 HUs and SSD >99 mm. The required number of SWs and the expected ET can be anticipated. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Prediction of coma and anisocoria based on computerized tomography findings in patients with supratentorial intracerebral hemorrhage.

    Science.gov (United States)

    Song, Zhi; Zheng, Wen; Zhu, Haixia; Chen, Yiwei; Fan, Xuejun; Hou, Deren; Deng, Hao

    2012-07-01

    Coma and anisocoria are the two common signs of a crucial state of neurological dysfunction. The ability to forecast the occurrence of these conditions would help clinicians make clinical risk assessments and decisions. From October 2006 to September 2008, 118 patients with supratentorial intracerebral hemorrhage (SICH) were enrolled in this retrospective investigation. Patients were distributed into 3 groups according to occurrence of the signs of coma and/or anisocoria in the observation unit during a 30-day period. Group 1 included 52 patients who had normal or impaired consciousness, group 2 included 27 patients who had coma with no anisocoria and group 3 consisted of 39 patients who had coma with anisocoria. The clinical characteristics and parameters on computerized tomography (CT) findings were compared using univariate analysis to determine the factors that were related to the level of consciousness. Logistic regression models established the predictive equations for coma and anisocoria. Univariate analysis revealed that hematoma volume, the score of intraventricular hemorrhage (IVH score) and the amplitude of midline shift were the factors related to coma and anisocoria. Mean hematoma volume was 24.0 ± 13.0 ml, 53.6 ± 12.6 ml and 80.5 ± 24.6 ml, the mean amplitudes of midline shift were 1.3 ± 2.0 mm, 5.9 ± 4.9 mm and 10.1 ± 5.5 mm, and the mean IVH score was 0.8 ± 1.3, 3.3 ± 3.3 and 5.9 ± 3.4 in groups 1, 2 and 3, respectively. Multivariate analysis showed that hematoma volume and IVH score were independent prognostic factors for coma and anisocoria. The predictive equations for coma and anisocoria were LogitP = 0.279X(HV) + 0.521X(IVH)-18.164 and LogitP = 0.125X(HV)+0.326X(IVH)-6.864, respectively. Hematoma volume and IVH score were the independent prognostic factors for coma and anisocoria. Logistic regression models established the fitted predictive equations, which could help clinicians make clinical risk assessments and decisions. Crown

  12. The role of renal scintigraphy and unenhanced helical computerized tomography in patients with ureterolithiasis.

    Science.gov (United States)

    Lorberboym, M; Kapustin, Z; Elias, S; Nikolov, G; Katz, R

    2000-04-01

    Unenhanced helical computerized tomography (UHCT) has recently evolved as an accurate imaging modality for determination of the presence or absence of ureterolithiasis in patients with acute flank pain. Functional renal scintigraphy is considered the gold standard for urinary tract obstruction. The objective of this study was to correlate the secondary signs of urinary obstruction on UHCT with findings of functional renal scintigraphy. UHCT was performed in 30 patients admitted to the emergency room with acute flank pain. All patients had a calcified urinary stone identified on UHCT. The location of each urinary stone was classified as ureteral or in the ureterovesical junction. The presence of secondary CT signs of ureteral obstruction was determined for each patient. After oral or intravenous hydration, a technetium-99m diethylene triamine penta-acetic acid renal scan was performed in all patients within 12 h of the CT scan. Follow-up delayed scintigraphic images were obtained at 2 h and 24 h in patients with evidence of ureteral obstruction. The sensitivity, specificity and predictive values of each possible combination of CT findings were determined by comparison with the scintigraphic results. The distal ureter was the most common location for a calculus on UHCT, followed in frequency by the ureterovesical junction, proximal ureter and mid-ureter. The renograms showed high-grade, unilateral obstruction in 12 patients, indeterminate scans in five patients and normal renograms in 13 patients. The sensitivities and specificities of individual CT findings ranged from 50% to 75% and from 8% to 69%, respectively. Perinephric stranding gave the highest positive predictive value (PPV) for obstruction (69% including indeterminate renograms). None of the individual CT findings showed a statistically significant correlation with scintigraphic findings. A combination of one or two positive CT findings had a PPV of only 25% for obstruction. A combination of three or four

  13. Are Hepatic Portal Venous System Components Distributed Equally in the Liver? A Multidetector Computerized Tomography Study

    Directory of Open Access Journals (Sweden)

    Bülent Yalçın

    2012-12-01

    Full Text Available Objective: We aimed to evaluate the relationships between the splenic index, right and left hepatic lobe volumes, diameters of splenic vein (SV, superior mesenteric vein (SMV and the portal vein (PV by Multidetector Computerized Tomography (MDCT. We also investigated indirect signs of portal venous flow pattern using these parameters.Material and Methods: Following their contrast thoracoabdominal and abdominal 64-MDCT examinations, the images of 100 cases (61 males and 39 females were evaluated retrospectively. For each case, the splenic index, total hepatic volume, left and right hepatic volumes were calculated on the post-contrast portal venous phase (50th sec images. Spearman correlation tests were carried out with the purpose of determining the relationships between the variables. Statistical significance level was set at p<0.005.Results: A statistically significant relation was demonstrated between the diameter of the SMV and right hepatic lobe volume (p<0.0001, and according to Pearson’s correlation analysis, a positive correlation of medium strength (r=0.36 was observed. A positive correlation was demonstrated between the diameter of the splenic vein and left hepatic lobe volume (r=0.36. Statistically significant relation between the diameters of the splenic vein and right hepatic lobe was not observed (p=0.62. A strong correlation between the left hepatic lobe volume and the splenic index (r=0.556 was observed.Conclusion: We observed a positive correlation and a significant relation between the diameter of the SMV and the right hepatic lobe, and a relation between the splenic vein and splenic index and both hepatic lobes. We believe that this situation is related to the streamline flow in the portal vein, and as demonstrated in the literature, the flow in the SMV is directed at the right lobe, whereas the splenic vein empties into the liver homogenously. Our study is the first study in the literature performed by multidetector CT

  14. Prediction of differential creatinine clearance in chronically obstructed kidneys by non-contrast helical computerized tomography

    Directory of Open Access Journals (Sweden)

    Ng C.F.

    2004-01-01

    Full Text Available PURPOSE: We investigate the use of non-contrast helical computerized tomography (NCHCT in the measurement of differential renal parenchymal volume as a surrogate for differential creatinine clearance (CrCl for unilateral chronically obstructed kidney. MATERIALS AND METHODS: Patients with unilateral chronically obstructed kidneys with normal contralateral kidneys were enrolled. Ultrasonography (USG of the kidneys was first done with the cortical thickness of the site with the most renal substance in the upper pole, mid-kidney, and lower pole of both kidneys were measured, and the mean cortical thickness of each kidney was calculated. NCHCT was subsequently performed for each patient. The CT images were individually reviewed with the area of renal parenchyma measured for each kidney. Then the volume of the slices was summated to give the renal parenchymal volume of both the obstructed and normal kidneys. Finally, a percutaneous nephrostomy (PCN was inserted to the obstructed kidney, and CrCl of both the obstructed kidney (PCN urine and the normal side (voided urine were measured two 2 after the relief of obstruction. RESULTS: From March 1999 to February 2001, thirty patients were enrolled into the study. Ninety percent of them had ureteral calculi. The differential CrCl of the obstructed kidney (%CrCl was defined as the percentage of CrCl of the obstructed kidney as of the total CrCl, measured 2 weeks after relief of obstruction. The differential renal parenchymal volume of the obstructed kidney (%CTvol was the percentage of renal parenchymal volume as of the total parenchymal volume. The differential USG cortical thickness of the obstructed kidney (%USGcort was the percentage of mean cortical thickness as of the total mean cortical thickness. The Pearson's correlation coefficient (r between %CTvol and %CrCl and that between %USGcort and %CrCl were 0.756 and 0.543 respectively. The regression line was %CrCl = (1.00 x %CTvol - 14.27. The %CTvol

  15. Comparison of Optical Coherence Tomography Angiography and Fluorescein Angiography for the Identification of Retinal Vascular Changes in Eyes With Diabetic Macular Edema.

    Science.gov (United States)

    Peres, Murilo Bertazzo; Kato, Renata Tiemi; Kniggendorf, Vinicius F; Cole, Emily D; Onal, Sumru; Torres, Elmar; Louzada, Ricardo; Belfort, Rubens; Duker, Jay S; Novais, Eduardo A; Regatieri, Caio V

    2016-11-01

    To compare the visualization of microaneurysms (MA) and the foveal avascular zone (FAZ) area using optical coherence tomography angiography (OCTA) versus fluorescein angiography (FA) in patients with diabetic macular edema (DME). Patients were prospectively recruited for same-day imaging on spectral-domain OCTA and FA. OCTA images were automatically segmented into superficial (sOCTA) and deep (dOCTA) capillary plexuses. The number of visible MAs and the FAZ area were compared between the two imaging modalities. Nineteen eyes of 10 patients were included. There was a statistically significant difference between MA counts for FA, sOCTA, and dOCTA (P = .002), and median MA counts were 14.5 (range: 2-43), 9.75 (range: 0-37.5), and 22.5 (range: 5.5-46.5), respectively. dOCTA showed significantly more MAs than sOCTA (P dOCTA revealed more MAs than FA (P = .06). There was a statistically significant difference between FAZ area for FA, sOCTA, and dOCTA (P = .046), and median FAZ areas were 0.444 (range: 0.1-0.689), 0.224 (range: 0.335-0.806), and 0.345 (range: 0.106-0.881), respectively. FA showed a significantly larger FAZ area than sOCTA (P = .04). Deep plexus OCTA can better identify microaneurysms compared to either sOCTA or FA. The FAZ area appears larger on FA in contrast to OCTA of both plexuses. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:1013-1019.]. Copyright 2016, SLACK Incorporated.

  16. The Prognosis of Patients With Nonobstructive Coronary Artery Disease Versus Normal Arteries Determined by Invasive Coronary Angiography or Computed Tomography Coronary Angiography: A Systematic Review.

    Science.gov (United States)

    Huang, Fang-Yang; Huang, Bao-Tao; Lv, Wen-Yu; Liu, Wei; Peng, Yong; Xia, Tian-Li; Wang, Peng-Ju; Zuo, Zhi-Liang; Liu, Rui-Shuang; Zhang, Chen; Gui, Yi-Yue; Liao, Yan-Biao; Chen, Mao; Zhu, Ye

    2016-03-01

    Limited data exist regarding the outcomes of patients with nonobstructive coronary artery disease (CAD) detected by computed tomography coronary angiography (CTCA) or invasive coronary angiography (ICA). Our aim was to compare the prognosis of patients with nonobstructive coronary artery plaques with that of patients with entirely normal arteries. The MEDLINE, Cochrane Library, and Embase databases were searched. Studies comparing the prognosis of individuals with nonobstructive CAD versus normal coronary arteries detected by CTCA or ICA were included. The primary outcome was major adverse cardiac events (MACE) including cardiac death, nonfatal myocardial infarction, hospitalization due to unstable angina or revascularization. A fixed effects model was chosen to pool the estimates of odds ratios (ORs). Forty-eight studies with 64,905 individuals met the inclusion criteria. Patients in the nonobstructive CAD arm had a significantly higher risk of MACE compared to their counterparts in the normal artery arm (pooled OR, 3.17, 95% confidence interval, 2.77-3.63). When excluding revascularization as an endpoint, hard cardiac composite outcomes were also more frequent among patients with nonobstructive CAD (pooled OR, 2.10; 95%CI, 1.79-2.45). All subgroups (age, sex, follow-up duration, different outcomes, diagnostic modality, and CAD risk factor) consistently showed a poorer prognosis with nonobstructive CAD than with normal arteries. When dividing the studies into a CTCA and ICA group for further analysis based on the indications for diagnostic tests, we also found nonobstructive CAD to be associated with a higher risk of MACE in both stable and acute chest pain. Patients with nonobstructive CAD had a poorer prognosis compared with their counterparts with normal arteries.

  17. Effectiveness of Adaptive Statistical Iterative Reconstruction for 64-Slice Dual-Energy Computed Tomography Pulmonary Angiography in Patients With a Reduced Iodine Load: Comparison With Standard Computed Tomography Pulmonary Angiography.

    Science.gov (United States)

    Lee, Ji Won; Lee, Geewon; Lee, Nam Kyung; Moon, Jin Il; Ju, Yun Hye; Suh, Young Ju; Jeong, Yeon Joo

    2016-01-01

    The aim of the study was to assess the effectiveness of the adaptive statistical iterative reconstruction (ASIR) for dual-energy computed tomography pulmonary angiography (DE-CTPA) with a reduced iodine load. One hundred forty patients referred for chest CT were randomly divided into a DE-CTPA group with a reduced iodine load or a standard CTPA group. Quantitative and qualitative image qualities of virtual monochromatic spectral (VMS) images with filtered back projection (VMS-FBP) and those with 50% ASIR (VMS-ASIR) in the DE-CTPA group were compared. Image qualities of VMS-ASIR images in the DE-CTPA group and ASIR images in the standard CTPA group were also compared. All quantitative and qualitative indices, except attenuation value of pulmonary artery in the VMS-ASIR subgroup, were superior to those in the VMS-FBP subgroup (all P ASIR images were superior to those of ASIR images in the standard CTPA group (P ASIR images of the DE-CTPA group than in ASIR images of the standard CTPA group (P = 0.001). The ASIR technique tends to improve the image quality of VMS imaging. Dual-energy computed tomography pulmonary angiography with ASIR can reduce contrast medium volume and produce images of comparable quality with those of standard CTPA.

  18. Analysis on the entrance surface dose and contrast medium dose at computed tomography and angiography in cardiovascular examination

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Hyun [Dept. of Cardiovascular Center, Yeocheon Jeonnam Hospital, Yeosu (Korea, Republic of); Han, Jae Bok; Choi, Nam Gil; Song, Jong Nam [Dept. of Radiological Science, Dongshin University, Naju (Korea, Republic of)

    2016-12-15

    This study aimed to identify dose reduction measures by retrospectively analyzing the entrance surface dose at computed tomography and angiography in cardiovascular examination and to contribute the patients with renal impairmend and a high probability of side effects to determine the inspection's direction by measuring the contrast usages actually to active actions for the dose by actually measuring the contrast medium dose. The CTDIvol value and air kerma value, which are the entrance surface doses of the two examinations, and the contrast medium dose depending on the number of slides were compared and analyzed. This study was conducted in 21 subjects (11 males; 10 females) who underwent Cardiac Computed Tomographic Angiography (CCTA) and Coronary Angiography (CAG) in this hospital during the period from May 2014 to May 2016. The subject's age was 48-85 years old (mean 65±10 years old), and the weight was 37.6~83.3 kg (mean 63±6 kg). Dose reduction could be expected in the cardiovascular examination using CCTA rather than in the examination using CAG. In terms of contrast medium dose, CAG used a smaller dose than CCTA. In particular, as the number of slides increases at CAG, the contrast medium dose increases. Therefore, in order to reduce the contrast medium dose, the number of slides suitable for the scan range must be selected.

  19. Multi-Modal Imaging Including Optical Coherence Tomography Angiography in Patients With Posterior Multifocal Placoid Pigment Epitheliopathy.

    Science.gov (United States)

    Werner, Jens Ulrich; Enders, Christian; Lang, Gerhard Klaus; Lang, Gabriele Elisabeth

    2017-09-01

    New imaging methods provide novel insights into the pathogenesis of acute posterior multifocal placoid pigment epitheliopathy (APMPPE). Four patients (eight eyes) in acute, subacute, and late phases of the disease were analyzed with multi-modal imaging methods including optical coherence tomography angiography (OCTA), structural OCT, fundus photography, and fundus autofluorescence. One patient was observed during the entire disease course. In acute and subacute phases of the disease, an early blockage in fluorescein angiography was found. OCTA showed perfusion defects in choriocapillaris and choroid slabs. During the course of disease, perfusion deficits observed in OCTA imaging resolved first in the choroid and then in the choriocapillaris slab. Multi-modal imaging including OCTA supports the thesis that the underlying pathology of APMPPE is an inflammatory impairment of the choroidal circulation with secondary damage to the outer retina. OCTA might be able to replace fluorescein and indocyanine angiography in the diagnostic work-up of APMPPE. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:727-733.]. Copyright 2017, SLACK Incorporated.

  20. Phase-insensitive optical coherence angiography of the choroid by 1-micrometer band swept-source optical coherence tomography

    Science.gov (United States)

    Yasuno, Yoshiaki; Hong, Youngjoo; Makita, Shuichi; Miura, Masahiro; Yatagai, Toyohiko

    2007-02-01

    Phase-insensitive optical coherence angiography also denoted as scattering optical coherence angiography (S-OCA), which uses optical coherence tomography (OCT) as an imaging engine and a software segmentation algorithm as a contrast engine, is a non-invasive alternative to indocyanine green angiography (ICGA). Three-dimensional in vivo vasculature of the human retina and choroid is visualized by S-OCA. A three-dimensional swept-source OCT with 1.05 um probe is built as the imaging engine of the S-OCT. The side lobes in the point spread function due to ripple peaks in the light source spectrum are eliminated by a software adaptive spectral shaping. Because of the deeper penetration of the 1.05 um probe to a scattering tissue, the in vivo human choroid and the scleral ring (scleral canal wall) are clearly visualized. The chromatic dispersion of the eye is automatically canceled in the manner of minimization of the information entropy of an OCT image. An intensity based levelset segmentation algorithm was developed for the enhanced visualization of the three-dimensional structure of the retinal and choroidal vascular network. This algorithm successfully visualizes the vascular networks of the in vivo human macula and optic nerve head.

  1. Computed tomography angiography spot sign predicts intraprocedural aneurysm rupture in subarachnoid hemorrhage.

    Science.gov (United States)

    Burkhardt, Jan-Karl; Neidert, Marian Christoph; Stienen, Martin Nikolaus; Schöni, Daniel; Fung, Christian; Roethlisberger, Michel; Corniola, Marco Vincenzo; Bervini, David; Maduri, Rodolfo; Valsecchi, Daniele; Tok, Sina; Schatlo, Bawarjan; Bijlenga, Philippe; Schaller, Karl; Bozinov, Oliver; Regli, Luca

    2017-07-01

    To analyze whether the computed tomography angiography (CTA) spot sign predicts the intraprocedural rupture rate and outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). From a prospective nationwide multicenter registry database, 1023 patients with aneurysmal subarachnoid hemorrhage (aSAH) were analyzed retrospectively. Descriptive statistics and logistic regression analysis were used to compare spot sign-positive and -negative patients with aneurysmal intracerebral hemorrhage (aICH) for baseline characteristics, aneurysmal and ICH imaging characteristics, treatment and admission status as well as outcome at discharge and 1-year follow-up (1YFU) using the modified Rankin Scale (mRS). A total of 218 out of 1023 aSAH patients (21%) presented with aICH including 23/218 (11%) patients with spot sign. Baseline characteristics were comparable between spot sign-positive and -negative patients. There was a higher clip-to-coil ratio in patients with than without aICH (both spot sign positive and negative). Median aICH volume was significantly higher in the spot sign-positive group (50 ml, 13-223 ml) than in the spot sign-negative group (18 ml, 1-416; p sign-positive aICH thus were three times as likely as those with spot sign-negative aICH to show an intraoperative aneurysm rupture [odds ratio (OR) 3.04, 95% confidence interval (CI) 1.04-8.92, p = 0.046]. Spot sign-positive aICH patients showed a significantly worse mRS at discharge (p = 0.039) than patients with spot sign-negative aICH (median mRS 5 vs. 4). Logistic regression analysis showed that the spot sign was an aICH volume-dependent predictor for outcome. Both spot sign-positive and -negative aICH patients showed comparable rates of hospital death, death at 1YFU and mRS at 1YFU. In this multicenter data analysis, patients with spot sign-positive aICH showed higher aICH volumes and a higher rate of intraprocedural aneurysm rupture, but comparable long-term outcome to spot sign-negative a

  2. In vivo determination of urinary stone composition using dual energy computerized tomography with advanced post-acquisition processing.

    Science.gov (United States)

    Zilberman, D E; Ferrandino, M N; Preminger, G M; Paulson, E K; Lipkin, M E; Boll, D T

    2010-12-01

    We assessed whether dual energy computerized tomography with advanced post-image processing can accurately differentiate urinary calculi composition in vivo. A total of 25 patients scheduled to undergo ureteroscopic/percutaneous nephrolithotomy were prospectively identified. Dual energy computerized tomography was performed using 64-slice multidetector computerized tomography. Novel post-processing (DECTSlope) used pixel by pixel analyses to generate data sets grayscale encoding ratios of relative differences in attenuation of low (DECT80 kVp) and high energy (DECT140 kVp) series. Surgical extraction and Fourier spectroscopy resulted in 82 calculi. Of these stones 51 showed minor admixtures (uric acid, ammonium urate, struvite, calcium oxalate monohydrate and brushite) and 31 were polycrystalline (mixtures of calcium oxalate monohydrate/dihydrate and calcium phosphate). Analyses identified stone clusters of equal composition and distinct attenuation descriptors on DECT140 kVp, DECT80 kVp and DECTSlope. Iterative cross-validation of the 3 dual energy computerized tomography data sets was used to identify characteristic attenuation limits for each stone type. Attenuatio profiles showed substantial overlap among various stones on DECT140 kVp (uric acid 427.3±168.1 HU, ammonium urate 429.9±99.7 HU, struvite 480.2±123.5 HU, calcium oxalate monohydrate 852.4±301.4 HU, brushite 863.7±180.1 HU and polycrystalline 858.1±210.5 HU) and on DECT80 kVp (uric acid 493.6±182.8 HU, ammonium urate 591.5±157.9 HU, struvite 712.4±173.9 HU, calcium oxalate monohydrate 1,240.5±494.7 HU, brushite 1,532.1±273.1 HU and polycrystalline 1,358.7±316.8 HU). Statistically spectral separation was not sufficient to characterize stones unambiguously based on DECT140 kVp/DECT80 kVp attenuation. Analysis of attenuation showed sufficient spectral separation on DECTSlope (uric acid 14.9±10.9 U, ammonium urate 56.1±1.8 U, struvite 42.7±1.4 U, calcium oxalate monohydrate 62.8±1.8 U and

  3. 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.

  4. Computed tomography angiography with pulmonary artery thrombus burden and right-to-left ventricular diameter ratio after pulmonary embolism.

    Science.gov (United States)

    Ouriel, Kenneth; Ouriel, Richard L; Lim, Yeun J; Piazza, Gregory; Goldhaber, Samuel Z

    2017-02-01

    Purpose Computed tomography angiography is used for quantifying the significance of pulmonary embolism, but its reliability has not been well defined. Methods The study cohort comprised 10 patients randomly selected from a 150-patient prospective trial of ultrasound-facilitated fibrinolysis for acute pulmonary embolism. Four reviewers independently evaluated the right-to-left ventricular diameter ratios using the standard multiplanar reformatted technique and a simplified (axial) method, and thrombus burden with the standard modified Miller score and a new, refined Miller scoring system. Results The intraclass correlation coefficient for intra-observer variability was .949 and .970 for the multiplanar reformatted and axial methods for estimating right-to-left ventricular ratios, respectively. Inter-observer agreement was high and similar for the two methods, with intraclass correlation coefficient of .969 and .976. The modified Miller score had good intra-observer agreement (intraclass correlation coefficient .820) and was similar to the refined Miller method (intraclass correlation coefficient .883) for estimating thrombus burden. Inter-observer agreement was also comparable between the techniques, with intraclass correlation coefficient of .829 and .914 for the modified Miller and refined Miller methods. Conclusions The reliability of computed tomography angiography for pulmonary embolism was excellent for the axial and multiplanar reformatted methods for quantifying the right-to-left ventricular ratio and for the modified Miller and refined Miller scores for quantifying of pulmonary artery thrombus burden.

  5. Coronary Computed Tomography Angiography in Combination with Coronary Artery Calcium Scoring for the Preoperative Cardiac Evaluation of Liver Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Jae Moon Choi

    2017-01-01

    Full Text Available Liver transplantation is the best treatment option for early-stage hepatocellular carcinoma, liver cirrhosis, fulminant liver failure, and end-stage liver diseases. Even though advances in surgical techniques and perioperative care have improved postoperative outcomes, perioperative cardiovascular complications are a leading cause of postoperative morbidity and mortality following liver transplantation. Ischemic coronary artery disease (CAD and cardiomyopathy are the most common cardiovascular diseases and could be negative predictors of postoperative outcomes in liver transplant recipients. Therefore, comprehensive cardiovascular evaluations are required to assess perioperative risks and prevent concomitant cardiovascular complications that would preclude good outcomes in liver transplant recipients. The two major types of cardiac computed tomography are the coronary artery calcium score (CACS and coronary computed tomography angiography (CCTA. CCTA in combination with the CACS is a validated noninvasive alternative to coronary angiography for diagnosing and grading the severity of CAD. A CACS > 400 is associated with significant CAD and a known important predictor of posttransplant cardiovascular complications in liver transplant recipients. In this review article, we discuss the usefulness, advantages, and disadvantages of CCTA combined with CACS as a noninvasive diagnostic tool for preoperative cardiac evaluation and for maximizing the perioperative outcomes of liver transplant recipients.

  6. MACULAR ATROPHY FINDINGS BY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY COMPARED WITH FUNDUS AUTOFLUORESCENCE IN TREATED EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

    Science.gov (United States)

    Takasago, Yukari; Shiragami, Chieko; Kobayashi, Mamoru; Osaka, Rie; Ono, Aoi; Yamashita, Ayana; Tsujikawa, Akitaka; Hirooka, Kazuyuki

    2017-11-28

    To compare the areas of choriocapillaris (CC) nonperfusion and macular atrophy (MA) in treated exudative age-related macular degeneration. This was a prospective, observational, cross-sectional study. Forty-four eyes exhibiting MA (42 patients with age-related macular degeneration), with a dry macula, underwent fundus autofluorescence and optical coherence tomography angiography. The area of MA detected by fundus autofluorescence and CC nonperfusion detected by optical coherence tomography angiography was measured using image analysis software. The rates of concordance between the MA and CC nonperfusion areas were calculated. We qualitatively and quantitatively compared the areas of MA and CC nonperfusion in age-related macular degeneration eyes. The mean areas of MA and CC nonperfusion were 5.95 ± 4.50 mm and 10.66 ± 7.05 mm, respectively (paired t-test, P age-related macular degeneration.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  7. Computerized flow and vessel wall analyses of coronary arteries for detection of non-calcified plaques in coronary CT angiography

    Science.gov (United States)

    Wei, Jun; Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Agarwal, Prachi; Hadjiiski, Lubomir; Kazerooni, Ella

    2016-03-01

    The buildup of non-calcified plaques (NCP) that are vulnerable to rupture in coronary arteries is a risk for myocardial infarction. We are developing a computer-aided detection (CADe) system to assist radiologists in detecting NCPs in cCTA. A major challenge of NCP detection is the large number of false positives (FPs) caused by the small sized coronary arteries, image noise and artifacts. In this study, our purpose is to design new image features to reduce FPs. A data set of 98 cCTA scans was retrospectively collected from patient files. We first used vessel wall analysis, in which topological features were extracted from vessel wall and fused with a support-vector machine, to identify the NCP candidates from the segmented coronary tree. Computerized flow dynamic (CFD) features that characterize the change in blood flow due to the presence of plaques and a vascular cross-sectional (VCS) feature that quantifies the presence of low attenuation region at the vessel wall were designed for FP reduction. Using a leave-one-out resampling method, a support vector machine classifier was trained to merge the features into a NCP likelihood score using the vessel wall features alone or in combination with the new CDF and VCS features. The performance of the new features in classification of true NCPs and FPs was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). Without the new CFD and VCS features, the test AUC was 0.84+/-0.01. The AUC was improved to 0.88+/-0.01 with the addition of the new features. The improvement was statistically significant (p < 0.001). The study indicated that the new flow dynamic and vascular cross-sectional features were useful for differentiation of NCPs from FPs in cCTA.

  8. 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.)

  9. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars

    Energy Technology Data Exchange (ETDEWEB)

    Acar, Buket; Kamburoglu, Kivanc [Dept. of Dentomaxillofacial Radiology, Faculty of Dentistry, Ankara University, Ankara (Turkmenistan); Tatar, Ilkan [Dept. of Anatomy, Faculty of Medicine, Hacettepe University, Ankara (Turkmenistan); Arikan, Volkan [Dept. of Anatomy, Faculty of Medicine, Hacettepe University, Ankara (Turkmenistan); Celik, Hakan Hamid [Dept. of Pediatric Dentistry, Faculty of Dentistry, Kirikkale Unversity, Ankara (Turkmenistan); Yuksel, Selcen [Dept. of Biostatistics, Faculty of Medicine, Yildirim Beyazit University, Ankara (Turkmenistan); Ozen, Tuncer [Dept. of Dentomaxillofacial Radiology, Gulhane Military Hospital, Dental Clinics, Ankara (Turkmenistan)

    2015-12-15

    This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images.Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth.

  10. Combined multimodal photoacoustic tomography, optical coherence tomography (OCT) and OCT based angiography system for in vivo imaging of multiple skin disorders in human(Conference Presentation)

    Science.gov (United States)

    Liu, Mengyang; Chen, Zhe; Sinz, Christoph; Rank, Elisabet; Zabihian, Behrooz; Zhang, Edward Z.; Beard, Paul C.; Kittler, Harald; Drexler, Wolfgang

    2017-02-01

    All optical photoacoustic tomography (PAT) using a planar Fabry-Perot interferometer polymer film sensor has been demonstrated for in vivo human palm imaging with an imaging penetration depth of 5 mm. The relatively larger vessels in the superficial plexus and the vessels in the dermal plexus are visible in PAT. However, due to both resolution and sensitivity limits, all optical PAT cannot reveal the smaller vessels such as capillary loops and venules. Melanin absorption also sometimes causes difficulties in PAT to resolve vessels. Optical coherence tomography (OCT) based angiography, on the other hand, has been proven suitable for microvasculature visualization in the first couple millimeters in human. In our work, we combine an all optical PAT system with an OCT system featuring a phase stable akinetic swept source. This multimodal PAT/OCT/OCT-angiography system provides us co-registered human skin vasculature information as well as the structural information of cutaneous. The scanning units of the sub-systems are assembled into one probe, which is then mounted onto a portable rack. The probe and rack design gives six degrees of freedom, allowing the multimodal optical imaging probe to access nearly all regions of human body. Utilizing this probe, we perform imaging on patients with various skin disorders as well as on healthy controls. Fused PAT/OCT-angiography volume shows the complete blood vessel network in human skin, which is further embedded in the morphology provided by OCT. A comparison between the results from the disordered regions and the normal regions demonstrates the clinical translational value of this multimodal optical imaging system in dermatology.

  11. Evaluation of novel computerized tomography scoring systems in human traumatic brain injury: An observational, multicenter study.

    Directory of Open Access Journals (Sweden)

    Eric Peter Thelin

    2017-08-01

    Full Text Available Traumatic brain injury (TBI is a major contributor to morbidity and mortality. Computerized tomography (CT scanning of the brain is essential for diagnostic screening of intracranial injuries in need of neurosurgical intervention, but may also provide information concerning patient prognosis and enable baseline risk stratification in clinical trials. Novel CT scoring systems have been developed to improve current prognostic models, including the Stockholm and Helsinki CT scores, but so far have not been extensively validated. The primary aim of this study was to evaluate the Stockholm and Helsinki CT scores for predicting functional outcome, in comparison with the Rotterdam CT score and Marshall CT classification. The secondary aims were to assess which individual components of the CT scores best predict outcome and what additional prognostic value the CT scoring systems contribute to a clinical prognostic model.TBI patients requiring neuro-intensive care and not included in the initial creation of the Stockholm and Helsinki CT scoring systems were retrospectively included from prospectively collected data at the Karolinska University Hospital (n = 720 from 1 January 2005 to 31 December 2014 and Helsinki University Hospital (n = 395 from 1 January 2013 to 31 December 2014, totaling 1,115 patients. The Marshall CT classification and the Rotterdam, Stockholm, and Helsinki CT scores were assessed using the admission CT scans. Known outcome predictors at admission were acquired (age, pupil responsiveness, admission Glasgow Coma Scale, glucose level, and hemoglobin level and used in univariate, and multivariable, regression models to predict long-term functional outcome (dichotomizations of the Glasgow Outcome Scale [GOS]. In total, 478 patients (43% had an unfavorable outcome (GOS 1-3. In the combined cohort, overall prognostic performance was more accurate for the Stockholm CT score (Nagelkerke's pseudo-R2 range 0.24-0.28 and the Helsinki CT score

  12. Carotid and vertebral artery dissections: examination strategies in MR imaging and MR angiography; Kraniozervikale Dissektionen: Untersuchungsstrategien in der MR-Tomographie und MR-Angiographie

    Energy Technology Data Exchange (ETDEWEB)

    Keller, E.; Flacke, S.; Sommer, T.; Brechtelsbauer, D.; Pauleit, D.; Textor, J.; Schild, H.H. [Radiologische Universitaetsklinik Bonn (Germany); Gieseke, J. [Philips Medizin Systeme, Bonn (Germany); Gass, S. [Neurologische Universitaetsklinik Bonn (Germany)

    1997-12-01

    Purpose: To define the diagnostic efficacy of MR imaging, `time of flight` (TOF) and phase contrast (PC) MR angiography in craniocervical arterial dissections. Material and methods: The MR examinations of 16 patients with proven arterial dissections (n=20) were retrospectively analysed by three independent readers. The MR protocol included T{sub 1}w spin echo sequences with and without fat saturation (SPIR), T{sub 2}w-turbo-spin echo, 2D- and 3D-TOF- and 3D-PC-MRA. The study was undertaken to assess the diagnostic sensitivity of each technique in detecting typical pathological features. Results: The overall sensitivity was best in 3D-PC-MRA; reaching 88% of all possible points. Intramural haematoma could be easily detected with T{sub 1}w spin echo with fat saturation (100%). Intimal flap and lumen narrowing was best defined with 3D-TOF-MRA in 86% resp. 96% and 3D-PC-MRA in 69% resp. 97%. 3D-PC-MRA was superior to all other sequences in 5 cases of aneurysmal dissection (100%). Conclusions: An accurate evaluation of craniocervical arterial dissections should rely on a combined protocol including T{sub 1}w spin echo with fat saturation and an axial 3D-MR angiography (if possible 3D-phase contrast MRA). (orig.) [Deutsch] Ziel: Die Studie untersucht die Aussagekraft der MR-Tomographie, der `time of flight` (TOF)- und der Phasenkontrast (PC)-MR-Angiographie bei kraniozervikalen Dissektionen. Material und Methoden: Retrospektiv wurden die MR-Untersuchungen von 16 Patienten mit 20 gesicherten Dissektionen ausgewertet. Das Untersuchungsprotokoll umfasste axiale T{sub 1}-gew. Spin-Echo-Sequenzen mit und ohne frequenzselektive Fettunterdrueckung (SPIR), T{sub 2}-gewichtete Turbo-Spin-Echo-Aufnahmen, eine 2D- und 3D-TOF-MRA sowie eine 3D-PC-MRA. Die einzelnen Verfahren wurden hinsichtlich der Diagnosestellung und der Erfassung typischer pathologischer Befunde durch drei unabhaengige Untersucher ausgewertet. Ergebnisse: Das beste Gesamtergebnis fuer alle Bewertungskriterien

  13. Accuracy of computerized tomography for the evaluation of mandibular sites prior to implant placement

    DEFF Research Database (Denmark)

    Sforza, Nicola Marco; Franchini, Federico; Lamma, Achille

    2007-01-01

    The objective of the present study was to observe the effect of positioning of the mandible on the accuracy of cross-sectional images obtained by reformatting computerized tomographic (CT) scans. An additional aim was to evaluate the ability of a software program (DentalVox, Era Scientific) to re...

  14. Catheter Angiography

    Medline Plus

    Full Text Available ... stents or evaluating a stent after implantation. detect injury to one or more arteries in the neck, ... of the radiation while soft tissue, such as muscle, fat and organs, allow more of the ... is called superselective angiography. Unlike computed tomography ( ...

  15. OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY REVEALS BLOOD FLOW IN CHOROIDAL NEOVASCULAR MEMBRANE IN REMISSION PHASE OF NEOVASCULAR AGE-RELATED MACULAR DEGENERATION.

    Science.gov (United States)

    Ichiyama, Yusuke; Sawada, Tomoko; Ito, Yuka; Kakinoki, Masashi; Ohji, Masahito

    2017-04-01

    The aim of the study was to investigate blood flow in choroidal neovascular membrane in remission phase of neovascular age-related macular degeneration using optical coherence tomography (OCT) angiography. OCT angiography was obtained in eyes with remission phase of neovascular age-related macular degeneration after treatments, defined as no exudative change (such as macular edema, subretinal fluid, and subretinal hemorrhage) observed in eyes without any treatment for neovascular age-related macular degeneration within the previous 6 months. Irregular blood flows shown in the segmentation of outer retina detected by OCT angiography were considered as blood flows in choroidal neovascular membrane. The vascular area and vessel density were obtained from OCT angiography images. Twenty eyes of 20 patients were included in this analysis. The blood flows in choroidal neovascular membrane were observed in all eyes (100%) using OCT angiography. The mean vascular area was 3.81 ± 3.41 mm and the mean vessel density of lesion was 28.9 ± 8.2%. The vessel density was significantly correlated with best-corrected visual acuity and duration of remission (best-corrected visual acuity: P = 0.008, r = -0.576; duration of remission: P = 0.017, r = -0.525, respectively). Optical coherence tomography angiography revealed that blood flows in choroidal neovascular membrane remained in eyes with clinically inactive neovascular age-related macular degeneration.

  16. Quality of abdominal computed tomography angiography: hand versus mechanical intravenous contrast administration in children

    Energy Technology Data Exchange (ETDEWEB)

    Ayyala, Rama S.; Lee, Edward Y. [Boston Children' s Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Zurakowski, David [Boston Children' s Hospital and Harvard Medical School, Departments of Anesthesiology and Surgery, Boston, MA (United States)

    2015-11-15

    Abdominal CT angiography has been increasingly used for evaluation of various conditions related to abdominal vasculature in the pediatric population. However, no direct comparison has evaluated the quality of abdominal CT angiography in children using hand versus mechanical administration of intravenous (IV) contrast agent. To compare hand versus mechanical administration of IV contrast agent in the quality of abdominal CT angiography in the pediatric population. We retrospectively reviewed the electronic medical record to identify pediatric patients (≤18 years) who had abdominal CT angiography between August 2012 and August 2013. The information obtained includes: (1) type of administration of IV contrast agent (hand [group 1] versus mechanical [group 2]), (2) size (gauge) of IV catheter, (3) amount of contrast agent administered and (4) rate of contrast agent administration (ml/s). Two reviewers independently performed qualitative and quantitative evaluation of abdominal CT angiography image quality. Qualitative evaluation of abdominal CT angiography image quality was performed by visual assessment of the degree of contrast enhancement in the region of interest (ROI) based on a 4-point scale. Quantitative evaluation of each CT angiography examination was performed by measuring the Hounsfield unit (HU) using an ROI within the abdominal aorta at two levels (celiac axis and the inferior mesenteric artery) for each child. Analysis of variance (ANOVA) using the F-test was applied to compare contrast enhancement within the abdominal aorta at two levels (celiac axis and inferior mesenteric artery) between hand administration and mechanical administration of IV contrast methods with adjustment for age. We identified 46 pediatric patients (24 male, 22 female; mean age 7.3 ± 5.5 years; range 5 weeks to 18 years) with abdominal CT angiography performed during the study period. Of these patients, 16 (35%; 1.7 ± 2.2 years; range 5 weeks to 5 years) had hand

  17. Computerized detection of noncalcified plaques in coronary CT angiography: Evaluation of topological soft gradient prescreening method and luminal analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Jun, E-mail: jvwei@umich.edu; Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Agarwal, Prachi; Kuriakose, Jean; Hadjiiski, Lubomir; Patel, Smita; Kazerooni, Ella [Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-08-15

    Purpose: The buildup of noncalcified plaques (NCPs) that are vulnerable to rupture in coronary arteries is a risk for myocardial infarction. Interpretation of coronary CT angiography (cCTA) to search for NCP is a challenging task for radiologists due to the low CT number of NCP, the large number of coronary arteries, and multiple phase CT acquisition. The authors conducted a preliminary study to develop machine learning method for automated detection of NCPs in cCTA. Methods: With IRB approval, a data set of 83 ECG-gated contrast enhanced cCTA scans with 120 NCPs was collected retrospectively from patient files. A multiscale coronary artery response and rolling balloon region growing (MSCAR-RBG) method was applied to each cCTA volume to extract the coronary arterial trees. Each extracted vessel was reformatted to a straightened volume composed of cCTA slices perpendicular to the vessel centerline. A topological soft-gradient (TSG) detection method was developed to prescreen for NCP candidates by analyzing the 2D topological features of the radial gradient field surface along the vessel wall. The NCP candidates were then characterized by a luminal analysis that used 3D geometric features to quantify the shape information and gray-level features to evaluate the density of the NCP candidates. With machine learning techniques, useful features were identified and combined into an NCP score to differentiate true NCPs from false positives (FPs). To evaluate the effectiveness of the image analysis methods, the authors performed tenfold cross-validation with the available data set. Receiver operating characteristic (ROC) analysis was used to assess the classification performance of individual features and the NCP score. The overall detection performance was estimated by free response ROC (FROC) analysis. Results: With our TSG prescreening method, a prescreening sensitivity of 92.5% (111/120) was achieved with a total of 1181 FPs (14.2 FPs/scan). On average, six features

  18. Radiation conditions for computerized tomography: determination and comparison; Condicoes de radiacao para tomografia computadorizada: determinacao e comparacoes

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Lucio das Chagas de

    2016-07-01

    Radiology is the practice in which radiation beams, usually radiation X are used to produce an image of the human body in order to obtain a diagnosis, for example, to evaluate a pathological condition by computerized tomography (CT). Although the computerized tomography diagnostic potential is unquestionable, caution must be taken because the doses are almost always higher than the observed in conventional radiology procedures. The ionization chamber used for dosimetry in CT is a unsealed cylindrical chamber with 10 cm and 15 cm of sensitive length. A typical characteristics of this camera is its uniform response to radiation incident at all angles around its axis. The revised edition of IEC 61267 (2005) brought as an innovation the radiation conditions for computed tomography, RQT, that simulate non-attenuated beam and are used in special CT applications. This study aims to establish the necessary conditions to obtain radiation pattern beam computed tomography, RQT, and a calibration laboratory implementation for pencil ionization chambers used in the beam dosimetry produced by these scanners in the Metrology National Laboratory of Ionizing Radiation (LNMRI). In the implementation of RQT conditions we were found that the ratio of kerma rates in the air, with or without additional filtration equivalent to the first HVL (half-value layer), are in accordance with IEC 61267 (2005), which provides a range between 48.5% and 51.5% for each quality. The LNMRI characterized the radiation conditions of RQT series (IEC, 2005), obtaining a percentage of 49.6% for the RQT 8, 50% for the RQT 9 and 50,4% for the RQT 10. With the substitution of the total additional filtration RQT qualities, composed by Al + Cu and by a total filtration composed by copper (Cu) only, it can be seen the emergence of a similar RQT quality named Quality Copper Tomography - QCT. The results of the calibration, the RQT and QCT qualities, had expanded uncertainties with a confidence level 95.45%, less

  19. Using computerized tomography to determine ionospheric structures. Part 1, Notivation and basic approaches

    Energy Technology Data Exchange (ETDEWEB)

    Vittitoe, C.N.

    1993-08-01

    Properties of the ionosphere are reviewed along with its correlations with other geophysical phenomena and with applications of ionospheric studies to communication, navigation, and surveillance systems. Computer tomography is identified as a method to determine the detailed, three-dimensional distribution of electron density within the ionosphere. Several tomography methods are described, with a basic approach illustrated by an example. Limitations are identified.

  20. The Pattern of significant lesions found in computerized tomography scan of recurrent seizure patients at a center in Enugu, Nigeria.

    Science.gov (United States)

    Ezeala-Adikaibe, A B; Ohaegbulam, S C; Ndubuisi, C A

    2017-10-01

    Seizures are common reasons for neurologic consultations and investigations. In the absence of magnetic resonance imaging, computerized tomography scanning of the brain is a reliable and cheaper alternative. Little is known about the pattern of brain lesions in patients with recurrent seizures in Nigeria. To determine the pattern of significant intracerebral lesions in patients presenting with recurrent seizures in a tertiary hospital in Enugu. All the medical and computer tomography records of patients with a clinical diagnosis of recurrent seizures were reviewed. The study duration was 11 years (January 2003 to December 2013). Relevant data were obtained and statistical analysis was done using SPSS version 19 and GraphPad Prism 6. The diagnostic yield of CT was 55.1%. Twenty (9.3%) individuals had two lesions each. The significant findings were tumors (20.4%), encephalomalacia (18.9%) and strokes (7.7% (ischemic stroke, 4.1%, intracerebral hemorrhage, 3.1%, subarachnoid hemorrhage/intraventricular hemorrhage, 0.5%). Hydrocephalus (HCP) was found in 18 (9.2%) cases, and 30% of them occurred together with other lesions. The diagnostic yield increased with age reaching 84.4% from the age of 60 years. Only patients with encephalomalacia were statistically older than those with normal imaging. Computed tomography scan has a high diagnostic yield, especially in elderly patients with recurrent generalized seizures. Brain tumors, encephalomalacia, and HCP are most common causes of recurrent seizures in the adults.

  1. Double-contrast, single-phase computed tomography angiography for ruling out left atrial appendage thrombus prior to atrial fibrillation ablation

    NARCIS (Netherlands)

    Teunissen, Cas; Habets, Jesse; Velthuis, BK; Cramer, Maarten J; Loh, KP

    Prior to atrial fibrillation (AF) ablation, computed tomography angiography (CTA) is increasingly used for left atrial appendage (LAA) thrombus detection. LAA filling defects on CTA may represent thrombus or incomplete contrast mixing with blood. A pre-bolus of contrast material with delay before

  2. Diagnostic accuracy of 320-row multidetector computed tomography coronary angiography in the non-invasive evaluation of significant coronary artery disease

    NARCIS (Netherlands)

    F.R. de Graaf (Fleur); J.D. Schuijf (Joanne); J.E. van Velzen (Joella); L.J. Kroft (Lucia); A. de Roos (Albert); J.H.C. Reiber (Johan); H. Boersma (Eric); M.J. Schalij (Martin Jan); F. Spanó (Fabrizio); J.W. Jukema (Jan Wouter); E.E. van der Wall (Ernst); J.J. Bax (Jeroen)

    2010-01-01

    textabstractAims Multidetector computed tomography coronary angiography (CTA) has emerged as a feasible imaging modality for non-invasive assessment of coronary artery disease (CAD). Recently, 320-row CTA systems were introduced, with 16 cm anatomical coverage, allowing image acquisition of the

  3. Assessment of coronary artery disease using coronary computed tomography angiography in patients with aortic valve stenosis referred for surgical aortic valve replacement

    DEFF Research Database (Denmark)

    Larsen, Linnea Hornbech; Kofoed, K Fuglsang; Dalsgaard, M

    2013-01-01

    BACKGROUND: In patients referred for aortic valve replacement (AVR) a pre-surgical assessment of coronary artery disease is mandatory to determine the possible need for additional coronary artery bypass grafting. The diagnostic accuracy of coronary computed tomography angiography (coronary CTA) w...... with low age, no chronic obstructive lung disease, NYHA function class...

  4. Thirteen-Year Evaluation of Highly Cross-Linked Polyethylene Articulating With Either 28-mm or 36-mm Femoral Heads Using Radiostereometric Analysis and Computerized Tomography

    DEFF Research Database (Denmark)

    Nebergall, Audrey K; Greene, Meridith E; Rubash, Harry E

    2016-01-01

    is a concern with this material through the use of plain radiographs and computerized tomography (CT). METHODS: All patients received a Longevity HXLPE liner with tantalum beads and either a 28-mm or 36-mm femoral head. Twelve patients (6 in each head size group) agreed to return for 13-year RSA, plain...

  5. Diagnostic performance comparison of the Chartis System and high-resolution computerized tomography fissure analysis for planning endoscopic lung volume reduction

    NARCIS (Netherlands)

    Gompelmann, Daniela; Eberhardt, Ralf; Slebos, Dirk-Jan; Brown, Matthew S.; Abtin, Fereidoun; Kim, Hyun J.; Holmes-Higgin, Debby; Radhakrishnan, Sri; Herth, Felix J. F.; Goldin, Jonathan

    Background and objective Endobronchial valve (EBV) therapy is optimized in patients who demonstrate little or no collateral ventilation (CV). The accuracy of the Chartis System and visual assessment of high-resolution computerized tomography (HRCT) fissure completeness by a core radiology laboratory

  6. Dose profile measurement in computerized axial tomography equipment using thermoluminescent dosemeters; Medicion del perfil de dosis en equipos de tomografia axial computarizada usando dosimetros termoluminiscentes

    Energy Technology Data Exchange (ETDEWEB)

    Azorin V, J.C.; Falcony, C.; Azorin N, J. [Centro de Investigacion en Ciencia y Tecnologia Avanzada, IPN, 07000 Mexico D.F. (Mexico)

    2000-07-01

    In this work are presented the results about measuring the radiation dose profile in two equipment of computerized axial tomography (Tac). Thermoluminescent dosemeters (Dtl) of LiF, Mg, Cu, P + Ptfe in form of disks were used which were developed and made in Mexico. The results showed that Dtl are appropriated for these type of studies. (Author)

  7. Rare bilateral C6 spondylolysis and spondylolisthesis in an adolescent athlete: evaluation with magnetic resonance imaging and multidetector computerized tomography.

    Science.gov (United States)

    Amin, Mohammed F; Mollano, Anthony V; Weinstein, Stuart L; El-Khoury, George Y

    2006-10-01

    Case report. To show a rare case of cervical spondylolysis and spondylolisthesis secondary to bilateral stress fractures at the pedicle laminar junction of C6 in a 16-year-old athlete playing high school baseball. The patient presented with 3 months of neck pain and intermittent right arm radicular symptoms. Plain radiographs and multidetector computerized tomography (CT) of the cervical spines. Plain radiographs revealed loss of lower cervical lordosis. Multidetector CT indicated bilateral C6 spondylolysis. Magnetic resonance imaging showed bilateral marrow edema at the pedicle laminar junction of C6. Treatment included placing his neck in a Philadelphia collar for 6 weeks. Follow-up CT revealed progression of healing. Early diagnosis and appropriate management of these cases are important to promote healing.

  8. [Role of computeric tomography and magnetic resonance imaging in diagnosis of inflammatory diseases of sacro-ileal joint].

    Science.gov (United States)

    Baĭramov, R B

    2012-05-01

    Sensitivity of computeric tomography (CT) and magnetic resonance imaging (MRI) for sacroileitis diagnosis was studied, optimal for MRI investigation was established. In 31 patients, owing obvious clinical signs of inflammatory sacroileitis (at average more than 5 mo duration of a low back pain) MRI of sacroiliac joint was conducted in a T1, T2 FS, 2D T2 FLASH regimes and after intravenous infusion of a contrast substance (gadolinium) - in a T1 FS regime, using system, owing a 1,5 T magnetic field intensity. The data obtained were compared with results of CT. Sacroileitis signs were revealed in 27 patients - according to CT data, and in 22 - MRI. CT have demonstrated as a more sensitive method of the bone erosion and sclerosis diagnosis, than MRI. MRI is more sensitive while revealing an active inflammatory process in the bone and joint space. While T1 FS application no additional information for sacroileitis diagnosis was obtained.

  9. Cardiac magnetic resonance and computed tomography angiography for clinical imaging of stable coronary artery disease. Diagnostic classification and risk stratification

    Science.gov (United States)

    Korosoglou, Grigorios; Giusca, Sorin; Gitsioudis, Gitsios; Erbel, Christian; Katus, Hugo A.

    2014-01-01

    Despite advances in the pharmacologic and interventional treatment of coronary artery disease (CAD), atherosclerosis remains the leading cause of death in Western societies. X-ray coronary angiography has been the modality of choice for diagnosing the presence and extent of CAD. However, this technique is invasive and provides limited information on the composition of atherosclerotic plaque. Coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) have emerged as promising non-invasive techniques for the clinical imaging of CAD. Hereby, CCTA allows for visualization of coronary calcification, lumen narrowing and atherosclerotic plaque composition. In this regard, data from the CONFIRM Registry recently demonstrated that both atherosclerotic plaque burden and lumen narrowing exhibit incremental value for the prediction of future cardiac events. However, due to technical limitations with CCTA, resulting in false positive or negative results in the presence of severe calcification or motion artifacts, this technique cannot entirely replace invasive angiography at the present time. CMR on the other hand, provides accurate assessment of the myocardial function due to its high spatial and temporal resolution and intrinsic blood-to-tissue contrast. Hereby, regional wall motion and perfusion abnormalities, during dobutamine or vasodilator stress, precede the development of ST-segment depression and anginal symptoms enabling the detection of functionally significant CAD. While CT generally offers better spatial resolution, the versatility of CMR can provide information on myocardial function, perfusion, and viability, all without ionizing radiation for the patients. Technical developments with these 2 non-invasive imaging tools and their current implementation in the clinical imaging of CAD will be presented and discussed herein. PMID:25147526

  10. Study on choroidal neovascularization with anti-VEGF treatment in the mouse retina using optical coherence tomography angiography (Conference Presentation)

    Science.gov (United States)

    Park, Jang Ryul; Choi, WooJhon; Kim, Jaeryung; Hong, Hye Kyong; Kim, Yongjoo; Hwang, Yoonha; Park, Sang Jun; Woo, Se Joon; Kim, Pilhan; Park, Kyu Hyung; Koh, Gou Young; Oh, Wang-Yuhl

    2017-02-01

    To understand the pathogenesis of ophthalmic disease, utilizing small animal models such as mouse is necessary because of their ease of maintenance and availability. For identifying pathophysiology and drug development of retinal diseases in mouse model, optical coherence tomography angiography (OCTA) is promising imaging modality visualizing not only microstructure but also microvasculature. In this study, we serially imaged 3D structure and angiography of laser-induced choroidal neovascularization (CNV) in the mouse retina with/without anti-VEGF treatment. Also, the volume changes of CNV and avascular region in choroid layer are measured for identifying effects of anti-VEGF. A lab-built high-speed OCTA prototype using the wavelength-swept laser centered at 1040 nm with 230 kHz A-scan rate acquired 3-D volumetric data consisted of 1024 x 1024 x 3 A-scans. The OCTA scanned 1.7 mm x 1.7 mm area around ONH. For obtaining angiography, amplitude decorrelation from 3 consecutive B-scans at each position was generated. Seven days after the laser photocoagulation at mouse retina for generation of the laser-induced CNV, intravitreal administration of Fc and VEGF-Trap was given in the therapeutic arm. The OCTA were performed at 6, 14, 21 and 35 days after laser photocoagulation. Vasculatures of inner retina, outer retina and choroid layers were separately visualized after RPE flattening and layer segmentation. To investigate therapeutic effects of anti-VEGF treatment, the relative area and volume of CNV in outer retina layer is measured. Also, total volume of avascular zone surrounding the laser injury site in choroid layer is also analyzed.

  11. [Preoperative evaluation of multi-slice spiral computed tomography angiography in laparoscopic radical operation for colorectal carcinoma].

    Science.gov (United States)

    Deng, Runshu; Mo, Linyao; He, Xihua; Chen, Jianhua; Cai, Renjun; Wang, Zaiguo; Huang, Shichuan; Lu, Huanquan; Huang, Zhaolun; Wu, Zhiming

    2016-03-01

    To investigate the clinical application of 256 multi-slice spiral computed tomography angiography (MSCTA) technique in the preoperative evaluation of mesenteric angiography in order to provide a reference to vessel anatomy and dissociation in laparoscopic radical operation for colorectal carcinoma. Clinical data of 50 patients with colorectal cancer who underwent preoperative MSCTA+FDCT and laparoscopic curative operation at our hospital from October 2013 to March 2015 were collected (MSCTA group). The evaluation item was visualization of mesenteric artery, which was compared with the findings under laparoscopic surgery. Meanwhile, another 50 colorectal cancer patients undergoing laparoscopic radical operation by the same surgeon team without preoperative MSCTA examination were used as control(control group). Clinical data were compared between the two groups. MSCTA precisely and correctly demonstrated anatomy and variations of the mesenteric artery and relative nutrient vessel in carcinoma. The angiography reconstruction images were consistent with the visual anatomy and variation from laparoscopic findings, whose diagnostic conformity rate of 100%. As compared to control group, operative time was shorter [(195.0±23.2) minutes vs.(218.0±19.6) minutes, t=8.326, P=0.015], and blood loss was less[(168.1±18.8) ml vs. (206.5±14.3) ml, t=-19.369, P=0.002] in MSCTA group. Differences of number of harvested lymph node, postoperative complication morbidity, postoperative hospital stay and hospitalization cost were not significant between two groups(all P>0.05). Preoperative MSCTA can demonstrate anatomy and variations of the mesenteric artery precisely and correctly, thus it is beneficial to shorten the operation time and to reduce blood loss.

  12. Impact of an intra-cycle motion correction algorithm on overall evaluability and diagnostic accuracy of computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Pontone, Gianluca; Bertella, Erika; Baggiano, Andrea; Mushtaq, Saima; Loguercio, Monica; Segurini, Chiara; Conte, Edoardo; Beltrama, Virginia; Annoni, Andrea; Formenti, Alberto; Petulla, Maria; Trabattoni, Daniela; Pepi, Mauro [Centro Cardiologico Monzino, IRCCS, Milan (Italy); Andreini, Daniele; Montorsi, Piero; Bartorelli, Antonio L. [Centro Cardiologico Monzino, IRCCS, Milan (Italy); University of Milan, Department of Cardiovascular Sciences and Community Health, Milan (Italy); Guaricci, Andrea I. [University of Foggia, Department of Cardiology, Foggia (Italy)

    2016-01-15

    The aim of this study was to evaluate the impact of a novel intra-cycle motion correction algorithm (MCA) on overall evaluability and diagnostic accuracy of cardiac computed tomography coronary angiography (CCT). From a cohort of 900 consecutive patients referred for CCT for suspected coronary artery disease (CAD), we enrolled 160 (18 %) patients (mean age 65.3 ± 11.7 years, 101 male) with at least one coronary segment classified as non-evaluable for motion artefacts. The CCT data sets were evaluated using a standard reconstruction algorithm (SRA) and MCA and compared in terms of subjective image quality, evaluability and diagnostic accuracy. The mean heart rate during the examination was 68.3 ± 9.4 bpm. The MCA showed a higher Likert score (3.1 ± 0.9 vs. 2.5 ± 1.1, p < 0.001) and evaluability (94%vs.79 %, p < 0.001) than the SRA. In a 45-patient subgroup studied by clinically indicated invasive coronary angiography, specificity, positive predictive value and accuracy were higher in MCA vs. SRA in segment-based and vessel-based models, respectively (87%vs.73 %, 50%vs.34 %, 85%vs.73 %, p < 0.001 and 62%vs.28 %, 66%vs.51 % and 75%vs.57 %, p < 0.001). In a patient-based model, MCA showed higher accuracy vs. SCA (93%vs.76 %, p < 0.05). MCA can significantly improve subjective image quality, overall evaluability and diagnostic accuracy of CCT. (orig.)

  13. Role of 320-slice multislice computed tomography coronary angiography in the assessment of coronary artery stenosis

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Youssef

    2014-06-01

    Conclusion: In conclusion, MSCT coronary angiography is a very helpful and rapid non-invasive coronary imaging modality that was able to detect and grade coronary artery stenosis better than other noninvasive examinations used to detect CAD, such as exercise stress testing. Due to its very high negative predictive value, it may eliminate the need for invasive coronary procedures in the presence of normal coronary imaging.

  14. Graphics processing unit accelerated intensity-based optical coherence tomography angiography using differential frames with real-time motion correction.

    Science.gov (United States)

    Watanabe, Yuuki; Takahashi, Yuhei; Numazawa, Hiroshi

    2014-02-01

    We demonstrate intensity-based optical coherence tomography (OCT) angiography using the squared difference of two sequential frames with bulk-tissue-motion (BTM) correction. This motion correction was performed by minimization of the sum of the pixel values using axial- and lateral-pixel-shifted structural OCT images. We extract the BTM-corrected image from a total of 25 calculated OCT angiographic images. Image processing was accelerated by a graphics processing unit (GPU) with many stream processors to optimize the parallel processing procedure. The GPU processing rate was faster than that of a line scan camera (46.9 kHz). Our OCT system provides the means of displaying structural OCT images and BTM-corrected OCT angiographic images in real time.

  15. Diagnostic Performance of a Novel Method for Fractional Flow Reserve Computed from Noninvasive Computed Tomography Angiography (NOVEL-FLOW Study).

    Science.gov (United States)

    Chung, Ju-Hyun; Lee, Kyung Eun; Nam, Chang-Wook; Doh, Joon-Hyung; Kim, Hyung Il; Kwon, Soon-Sung; Shim, Eun Bo; Shin, Eun-Seok

    2017-08-01

    Coronary computed tomography angiography (CCTA)-derived fractional flow reserve from computed tomography (CT-FFR) may provide better diagnostic performance over CCTA alone, but the complexity of its method limits the use in clinical environment. The aim of the present study is to validate a newly developed vessel-length based computational fluid dynamics scheme for the computation of FFR based on CCTA data, compare them with invasively measured FFR, and evaluate its diagnostic performance with that of CCTA. One hundred seventeen patients from 4 medical institutions who had clinically indicated invasive coronary angiography for suspected coronary artery disease (CAD) were enrolled. Invasive FFR measurement was performed in 218 vessels and these measurements were regarded as the reference standard. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of CT-FFR on a per-vessel basis were 85.8%, 86.2%, 85.5%, 79.8%, and 90.3%, respectively, for CT-FFR ≤0.80, and 66.1%, 75.9%, 59.5%, 55.5%, and 78.8%, respectively, for CCTA ≥50%. A higher area under the receiver operating characteristic curve for CT-FFR was observed compared with CCTA (0.93 vs 0.74, p performed at a personal computer enhancing its applicability in clinical situation. The diagnostic accuracy of CT-FFR for the detection of functionally significant CAD was good and was superior to that of CCTA within a population of suspected CAD. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effectiveness and acceptability of a computerized decision support system using modified Wells criteria for evaluation of suspected pulmonary embolism.

    Science.gov (United States)

    Drescher, Frank S; Chandrika, Sharad; Weir, Ian D; Weintraub, Jeffrey T; Berman, Lewis; Lee, Ronald; Van Buskirk, Patricia D; Wang, Yun; Adewunmi, Adeshola; Fine, Jonathan M

    2011-06-01

    Ready availability of computed tomography (CT) angiography for evaluation of pulmonary embolism in emergency departments (EDs) is associated with a dramatic increase in the number of CT angiography tests. The aims of this study are to determine whether a validated prediction algorithm embedded in a computerized decision support system improves the positive yield rate of CT angiography for pulmonary embolism and is acceptable to emergency physicians. This study was conducted as a prospective interventional study with a retrospective preinterventional comparison group. The implementation of the computerized physician order entry-based computerized decision support system was associated with an overall increase in the positivity rate of from 8.3% (95% confidence interval [CI] 4.9% to 12.9%) preintervention to 12.7% (95% CI 8.6% to 17.7%) postintervention, with a difference of 4.4% (95% CI -1.4% to 10.1%). A total of 404 patients were eligible for inclusion. Physician nonadherence to the computerized decision support system occurred in 105 (26.7%) cases. Fifteen patients underwent CT angiography despite low Wells score and negative D-dimer result, all of whose results were negative for pulmonary embolism. Emergency physicians did not order CT angiography for 44 patients despite high pretest probability, with one receiving a diagnosis of pulmonary embolism on a subsequent visit and another, of DVT. When emergency physicians adhered to the computerized decision support system for the evaluation of suspected pulmonary embolism, a higher yield of CT angiography for pulmonary embolism occurred, with 28 positive results of 168 CT angiography tests (16.7%; 95% CI 11.4% to 23.2%) and a difference compared with preintervention of 8.4% (95% CI 1.7% to 15.4%). Physicians cited the time required to apply the computerized decision support system and a preference for intuitive judgment as reasons for not adhering to the computerized decision support system. Use of an evidence

  17. Assessment of the feeding arteries by three-dimensional computed tomography angiography prior to multi-arterial infusion chemotherapy for lung cancer

    OpenAIRE

    YE, XIAO-DAN; YUAN, ZHENG; YE, JIAN-DING; XIAO, XIANG-SHENG

    2012-01-01

    The aim of this study was to evaluate the efficacy of multi-detector row helical computed tomography (MDCT) angiography in the detection of feeding arteries prior to multi-arterial infusion for lung cancer. A total of 59 consecutive patients (44 males and 15 females; age range, 27–86 years; median age, 62 years) with non-small cell lung cancer underwent MDCT angiography of the thorax prior to multi-arterial infusion for lung cancer. Findings on CT angiograms, including CT scans, maximum inten...

  18. The multidetector computed tomography angiography (MDCTA) in the diagnosis of splenic artery aneurysm and pseudoaneurysm

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca; Mallarini, Giorgio (Dept. of Radiology, Azienda Ospedaliero Universitaria (AOU), Cagliari (Italy)), email: lucasaba@tiscali.it; Anzidei, Michele; Lucatelli, Pierleone (Dept. of Radiological Sciences, Univ. of Rome La Sapienza, Rome (Italy))

    2011-06-15

    Splenic artery aneurysm is the most frequent visceral artery aneurysm and rupture of the aneurysm is associated with a high mortality rate. It is important to discriminate between a true aneurysm and a pseudoaneurysm that may be caused by pancreatitis, iatrogenic and postoperative causes, trauma and peptic ulcer disease. Multidetector-row CT angiography (MDCTA) allows detailed visualization of the vascular anatomy and may allow identification of aneurysms and pseudoaneurysms that affect the splenic artery. The objective of this article is to provide a review of the general characteristics of splenic artery aneurysms and pseudoaneurysms and to describe the findings of MDCTA

  19. The potential of positron emission tomography/computerized tomography (PET/CT) scanning as a detector of high-risk patients with oral infection during preoperative staging.

    Science.gov (United States)

    Yamashiro, Keisuke; Nakano, Makoto; Sawaki, Koichi; Okazaki, Fumihiko; Hirata, Yasuhisa; Takashiba, Shogo

    2016-08-01

    It is sometimes difficult to determine during the preoperative period whether patients have oral infections; these patients need treatment to prevent oral infection-related complications from arising during medical therapies, such as cancer therapy and surgery. One of the reasons for this difficulty is that basic medical tests do not identify oral infections, including periodontitis and periapical periodontitis. In this report, we investigated the potential of positron emission tomography/computerized tomography (PET/CT) as a diagnostic tool in these patients. We evaluated eight patients during the preoperative period. All patients underwent PET/CT scanning and were identified as having the signs of oral infection, as evidenced by (18)F-fludeoxyglucose (FDG) localization in the oral regions. Periodontal examination and orthopantomogram evaluation showed severe infection or bone resorption in the oral regions. (18)F-FDG was localized in oral lesions, such as severe periodontitis, apical periodontitis, and pericoronitis of the third molar. The densities of (18)F-FDG were proportional to the degree of inflammation. PET/CT is a potential diagnostic tool for oral infections. It may be particularly useful in patients during preoperative staging, as they frequently undergo scanning at this time, and those identified as having oral infections at this time require treatment before cancer therapy or surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Computerized tomography using monoenergetic X-ray; Tomografia computadorizada com raios-X monoenergetico

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ernande B. da [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Dept. de Fisica; Lopes, Ricardo T.; Ladeira, Carlos L. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Instrumentacao Nuclear

    1996-12-31

    The use of filters place in X-ray beam to produce quasi-monoenergetic radiation and its utilization in tomography are described. The filters are 100{mu}m of Cu, 25 and 50{mu}m of Rh and filters prepared with resins, 40 mg/cm{sup 2}-Cd. A comparison of the acquired images is presented 3 refs., 5 figs.

  1. 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.)

  2. Computerized tomography magnified bone windows are superior to standard soft tissue windows for accurate measurement of stone size: an in vitro and clinical study.

    Science.gov (United States)

    Eisner, Brian H; Kambadakone, Avinash; Monga, Manoj; Anderson, James K; Thoreson, Andrew A; Lee, Hang; Dretler, Stephen P; Sahani, Dushyant V

    2009-04-01

    We determined the most accurate method of measuring urinary stones on computerized tomography. For the in vitro portion of the study 24 calculi, including 12 calcium oxalate monohydrate and 12 uric acid stones, that had been previously collected at our clinic were measured manually with hand calipers as the gold standard measurement. The calculi were then embedded into human kidney-sized potatoes and scanned using 64-slice multidetector computerized tomography. Computerized tomography measurements were performed at 4 window settings, including standard soft tissue windows (window width-320 and window length-50), standard bone windows (window width-1120 and window length-300), 5.13x magnified soft tissue windows and 5.13x magnified bone windows. Maximum stone dimensions were recorded. For the in vivo portion of the study 41 patients with distal ureteral stones who underwent noncontrast computerized tomography and subsequently spontaneously passed the stones were analyzed. All analyzed stones were 100% calcium oxalate monohydrate or mixed, calcium based stones. Stones were prospectively collected at the clinic and the largest diameter was measured with digital calipers as the gold standard. This was compared to computerized tomography measurements using 4.0x magnified soft tissue windows and 4.0x magnified bone windows. Statistical comparisons were performed using Pearson's correlation and paired t test. In the in vitro portion of the study the most accurate measurements were obtained using 5.13x magnified bone windows with a mean 0.13 mm difference from caliper measurement (p = 0.6). Measurements performed in the soft tissue window with and without magnification, and in the bone window without magnification were significantly different from hand caliper measurements (mean difference 1.2, 1.9 and 1.4 mm, p = 0.003, window settings with magnification. For uric acid calculi the measurement error was observed only in standard soft tissue window settings. In vivo 4.0x

  3. Coronary optical coherence tomography: minimally invasive virtual histology as part of targeted post-mortem computed tomography angiography.

    Science.gov (United States)

    Adlam, David; Joseph, Shiju; Robinson, Claire; Rousseau, Clement; Barber, Jade; Biggs, Mike; Morgan, Bruno; Rutty, Guy

    2013-09-01

    Social, cultural and practical barriers to conventional invasive autopsy have led to considerable interest in the development of minimally invasive radiological techniques as an alternative to the invasive autopsy for determining the cause of death. Critical to accurate diagnosis in this context is detailed examination of coronary anatomy and pathology. Current computed tomography and magnetic resonance imaging approaches have significantly advanced minimally invasive autopsy practice but have limited spatial resolution. This prohibits assessment at a microscopic level, meaning that histological assessment is still required for detailed analysis of, for example, coronary plaque rupture or dissection. Coronary optical coherence tomography (OCT) is used in the living during percutaneous coronary interventions to provide high-resolution coronary imaging, but this technique for obtaining virtual histology has not, to date, been translated into minimally invasive autopsy practice. We present a first description of minimally invasive post-mortem coronary OCT and discuss the potential for this technique to advance current practice.

  4. Catheter Angiography

    Medline Plus

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

  5. Imaging of Blood Flow in Cerebral Arteries with Dynamic Helical Computed Tomography Angiography (DHCTA) Using a 64-Row CT Scanner

    Energy Technology Data Exchange (ETDEWEB)

    Pekkola, J.; Kangasniemi, M. (Helsinki Medical Imaging Center, Helsinki Univ. Central Hospital, Helsinki (Finland))

    2009-08-15

    Background: Cerebral computed tomography angiography (CTA) depicts a structural image of intracranial arteries without providing much time-resolved information on blood flow dynamics. Current CT technology allows obtaining of rapidly repeated helical scans during the arterial contrast filling phase after an intravenous contrast injection. Purpose: To report our experience on dynamic CT imaging in determining the direction of contrast filling within proximal intracranial arteries of operated cerebral artery aneurysm patients. Such dynamic information can help detect vascular occlusion or severe spasm. The method is here referred to as dynamic helical CT angiography (DHCTA). Material and Methods: We retrospectively collected image and related technical data for 23 patients who underwent DHCTA and CTA during their first postoperative day after cerebral artery aneurysm surgery. For DHCTA, we had helically scanned a 4-cm tissue volume three times in succession with a 64-row CT scanner at intervals of 2.6 s during arterial contrast filling after an intravenous contrast injection. We assessed how well DHCTA succeeded in demonstrating the direction of contrast filling in the proximal intracranial arteries, evaluated clinically relevant structural information provided by DHCTA and CTA, and compared radiation doses for the two methods. Results: For 21 patients, DHCTA outlined the direction of contrast filling in proximal intracranial arteries. As to arterial spasm and residual filling of the operated aneurysm, CTA and DHCTA gave similar information. Radiation doses were higher (P<0.000001) for DHCTA than for CTA at 120 kV tube voltage. At 100 kV, the difference was smaller, but doses for DHCTA still exceeded (P<0.05) those for CTA. Conclusion: DHCTA gave dynamic information unobtainable with CTA and could prove useful in selected clinical settings

  6. Long-term prognostic performance of low-dose coronary computed tomography angiography with prospective electrocardiogram triggering.

    Science.gov (United States)

    Clerc, Olivier F; Kaufmann, Basil P; Possner, Mathias; Liga, Riccardo; Vontobel, Jan; Mikulicic, Fran; Gräni, Christoph; Benz, Dominik C; Fuchs, Tobias A; Stehli, Julia; Pazhenkottil, Aju P; Gaemperli, Oliver; Kaufmann, Philipp A; Buechel, Ronny R

    2017-11-01

    To assess long-term prognosis after low-dose 64-slice coronary computed tomography angiography (CCTA) using prospective electrocardiogram-triggering. We included 434 consecutive patients with suspected or known coronary artery disease referred for low-dose CCTA. Patients were classified as normal, with non-obstructive or obstructive lesions, or previously revascularized. Coronary artery calcium score (CACS) was assessed in 223 patients. Follow-up was obtained regarding major adverse cardiac events (MACE): cardiac death, myocardial infarction and elective revascularization. We performed Kaplan-Meier analysis and Cox regressions. Mean effective radiation dose was 1.7 ± 0.6 mSv. At baseline, 38% of patients had normal arteries, 21% non-obstructive lesions, 32% obstructive stenosis and 8% were revascularized. Twenty-nine patients (7%) were lost to follow-up. After a median follow-up of 6.1 ± 0.6 years, MACE occurred in 0% of patients with normal arteries, 6% with non-obstructive lesions, 30% with obstructive stenosis and 39% of those revascularized. MACE occurrence increased with increasing CACS (P 6 years for patients with normal coronary arteries. • Coronary CT angiography (CCTA) has an excellent long-term prognostic performance. • CCTA can accurately stratify cardiac risk according to coronary lesion severity. • A normal CCTA predicts freedom from cardiac events for >6 years. • Patients with a coronary calcium score of 0 may experience cardiac events. • CCTA allows for reclassification of cardiac risk compared with ESC SCORE.

  7. Noncontrast-Enhanced Magnetic Resonance Versus Computed Tomography Angiography in Preoperative Evaluation of Potential Living Renal Donors.

    Science.gov (United States)

    Blankholm, Anne Dorte; Pedersen, Bodil G; Østrat, Ernst Ø; Andersen, Gratien; Stausbøl-Grøn, Brian; Laustsen, Susse; Ringgaard, Steffen

    2015-11-01

    Living renal donors undergo an extensive examination program. These examinations should be as safe, gentle, and patient friendly as possible. To compare computed tomography angiography (CTA) and an extensive magnetic resonance imaging (MRI) protocol without contrast agents to observations from nephrectomy in living renal donors and to evaluate whether noncontrast-enhanced MRI can replace CTA for vessel assessment in living renal donors. CTA and MRI results were compared to observations from nephrectomy, which served as the reference standard. Fifty-one potential kidney donors underwent imaging, and 31 donated a kidney. Comparisons in sensitivity, specificity, and accuracy were made with respect to the number of arteries, early branching, and the number of veins. Agreement was assessed using Cohen's kappa. The exact McNemar's test was used to test for statistically significant differences. In the assessment of more than one renal artery, the sensitivity and specificity of MRI and CTA were high and in perfect agreement compared to observations from surgery. The results for both MRI and CTA were as follows: (sensitivity 100%/specificity100%/accuracy 100%/Kappa = 1/P = 1). When comparing the ability to test for early branching we found, MRI: (sensitivity 33%/specificity 100%/accuracy 87%/Kappa = 0.45/P = 1) and CTA: (sensitivity 50%/specificity 100%/accuracy 90%/Kappa = 0.62/P = 1). When used to depict supernumerary veins, we found MRI: (sensitivity60%/specifivity100%/accuracy 93%/Kappa = 0.72/P = 1), whereas CTA showed: (sensitivity 40%/specificity 96%/accuracy 87% Kappa = 0.43/P = 1). In conclusion, an optimized MRI protocol that includes noncontrast-enhanced magnetic resonance angiography can be substituted for CTA for preoperative assessment of the renal vessels before living donor nephrectomy. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  8. The Basilar Artery on Computed Tomography Angiography Score for Acute Basilar Artery Occlusion Treated with Mechanical Thrombectomy.

    Science.gov (United States)

    Yang, Haihua; Ma, Ning; Liu, Lian; Gao, Feng; Mo, Dapeng; Miao, Zhongrong

    2018-02-05

    Recently, the Basilar Artery on Computed Tomography Angiography (BATMAN) score predicts clinical outcome of acute basilar artery occlusion (BAO), yet there is no extensive external validation. The purpose of this study was to validate the prognostic value of BATMAN scoring system for the prediction of clinical outcome in patients with acute BAO treated with endovascular mechanical thrombectomy by using cerebral digital subtraction angiography (DSA). We analyzed the clinical and angiographic data of consecutive patients with acute BAO from March 2012 to November 2016. The BATMAN scoring system was used to assess the collateral status and thrombus burden. Thrombolysis in Cerebral Infarction (TICI) score 2b-3 was defined as successful recanalization. Receiver operating characteristic (ROC) curve was used to determine the area under the curve (AUC) and the optimum cutoff value. Multivariate regression analysis was used to identify the predictor of clinical outcome. This study included 63 patients with acute BAO who underwent mechanical thrombectomy. Of these patients, 90.5% (57/63) achieved successful recanalization (TICI, 2b-3) and 34.9% (22/63) had a favorable outcome (modified Rankin Scale score 0-2). ROC analysis indicated that the AUC of the BATMAN score was .722 (95% confidence interval [CI], .594-.827), and the optimal cutoff value was 3 (sensitivity = 72.73, specificity = 63.41). In multivariate logistic regression analysis, the BATMAN score higher than 3 was associated with favorable outcome (odds ratio, 5.214; 95% CI, 1.47-18.483; P = .011). The BATMAN score on DSA seems to predict the functional outcome in patients of acute BAO treated with mechanical thrombectomy. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  9. Coronary computed tomography angiography based assessment of endothelial shear stress and its association with atherosclerotic plaque distribution in-vivo.

    Directory of Open Access Journals (Sweden)

    Holger Hetterich

    Full Text Available PURPOSE: The relationship between low endothelial shear stress (ESS and coronary atherosclerosis is well established. ESS assessment so far depended on invasive procedures. The aim of this study was to demonstrate the relationship between ESS and coronary atherosclerosis by using non-invasive coronary computed tomography angiography (CTA for computational fluid dynamics (CFD simulations. METHODS: A total number of 7 consecutive patients with suspected coronary artery disease who received CTA and invasive angiography with IVUS analysis were included in this study. CTA examinations were performed using a dual-source scanner. These datasets were used to build a 3D mesh model. CFD calculations were performed using a validated CFD solver. The presence of plaque was assumed if the thickness of the intima-media complex exceeded 0.3 mm in IVUS. Plaque composition was derived by IVUS radiofrequency data analysis. RESULTS: Plaque was present in 32.1% of all analyzed cross-sections. Plaque prevalence was highest in areas of low ESS (49.6% and high ESS (34.8%. In parts exposed to intermediate-low and intermediate-high ESS few plaques were found (20.0% and 24.0% (p<0.001. Wall thickness was closely associated with local ESS. Intima-media thickness was 0.43±0.34 mm in low and 0.38±0.32 mm in high ESS segments. It was significantly lower when the arterial wall was exposed to intermediate ESS (0.25±0.18 mm and 0.28 ± 0.20 mm (p<0.001. Fibrofatty tissue was predominately found in areas exposed to low ESS (p≤0.023. CONCLUSIONS: In this study a close association of atherosclerotic plaque distribution and ESS pattern could be demonstrated in-vivo. Adding CFD analysis to coronary CTA offers the possibility to gather morphologic and physiologic data within one non-invasive examination.

  10. Planning deep inferior epigastric perforator flaps for breast reconstruction: a comparison between multidetector computed tomography and magnetic resonance angiography.

    Science.gov (United States)

    Cina, A; Barone-Adesi, L; Rinaldi, P; Cipriani, A; Salgarello, M; Masetti, R; Bonomo, L

    2013-08-01

    Deep inferior epigastric perforator (DIEP) flaps have become the state of the art in breast reconstruction. We compared the diagnostic performance of multidetector computed tomography (CTA) and magnetic resonance angiography (MRA) in DIEP flap planning. Twenty-three women (mean age 48.0 years, range 26-72 years) underwent preoperative blinded evaluation using 64-slice CTA and 1.5-T MRA. Perforator identification, measurement of their calibre, intramuscular course (IMC), assessment of direct venous connections (DVC) with main superficial veins, superficial venous communications (SVC) between the right and left hemi-abdomen and deep inferior epigastric artery (DIEA) branching type were performed. Surgery was carried out by the same team. Intraoperative findings were the standard of reference. Accuracy in identifying dominant perforators was 91.3 % for both techniques and mean error in calibre measurement 1.18 ± 0.35 mm for CTA and 1.63 ± 0.39 mm for MRA. Accuracy in assessing perforator IMCs was 97.1 % for CTA and 88.4 % for MRA, DVC 94.4 % for both techniques, SVC 91.3 % as well, and DIEA branching type 100 % for CTA and 91.3 % for MRA. Image acquisition and interpretation time was 21 ± 3 min for CTA (35 ± 5 min for MRA). In a strategy to optimise DIEP flap planning avoiding radiation exposure, MRA can be proposed alternatively to CTA. • Identification of deep inferior epigastric perforators (DIEP) is important before breast reconstruction. • Both CT and MR angiography are accurate in identifying DIEA perforator branches. • CTA and MRA are equivalent in demonstrating perforator-venous connections. • MRA can be proposed as an alternative to CTA in DIEP planning.

  11. Functional Testing or Coronary Computed Tomography Angiography in Patients With Stable Coronary Artery Disease

    DEFF Research Database (Denmark)

    Jørgensen, Mads E; Andersson, Charlotte; Nørgaard, Bjarne L

    2017-01-01

    electrocardiography or nuclear stress testing) from 2009 to 2015. Further use of noninvasive testing, invasive procedures, medications, and medical costs within 120 days were evaluated. Risks of long-term mortality and myocardial infarction (MI) were analyzed using adjusted Cox proportional hazard models. RESULTS....... 9.1%), aspirin (12.7% vs. 8.5%), invasive coronary angiography (14.7% vs. 10.1%), and percutaneous coronary intervention (3.8% vs. 2.1%); all p ....05), and a lower risk of MI (hazard ratio: 0.71; 95% confidence interval: 0.61 to 0.82). CONCLUSIONS: In stable patients undergoing initial evaluation for suspected coronary artery disease, coronary CTA was associated with greater use of statins, aspirin, and invasive procedures, and higher costs than functional...

  12. Use of multidetector computed tomography angiography of upper limb circulation in patients undergoing coronary artery bypass grafting surgery

    Directory of Open Access Journals (Sweden)

    Hasan B Altinsoy

    2017-01-01

    Full Text Available Objective: This study aimed to evaluate the bilateral forehand circulation using a 64-channel multidetector computed tomography (MDCT as a noninvasive method to define criteria for an upper extremity arterial anatomy and pathology prior to the use of arterial conduits. Materials and Methods: Fifty-five patients with coronary artery disease who underwent total arterial coronary artery bypass grafting (CABG were randomly selected for this prospective study. MDCT angiography was performed for 110 examinations of forearm and hand arterial anatomy. Prior to MDCT, Allen tests were performed in all patients with a normal result, except four. Thirteen patients had diabetes mellitus (DM, 8 had peripheral artery occlusive disease, and 19 had a history of smoking. Results: All arteries, including axillary, ulnar artery (UA and radial artery (RA, were clearly visualized in all patients. Upper extremity anatomical and pathological results were examined in 16 patients (29.1%. Severely calcified RA and/or UA were found in 6 patients who had a moderate renal failure. Nearly total occlusion of the RA was detected in another two patients. Focal intimal RA calcification was recorded in 1 female and 3 male patients. Ten patients who had severe calcification or intimal sclerosis of the upper extremity arteries had DM. The remaining patients had normal forehand arterial circulation. A persistent median artery with the absence of radial and ulnar arteries and a high bifurcation of RA from the brachial artery was detected as an anatomic variation in seven patients (12.7%. Conclusions: The major advantages of MDCT angiography are its non-invasiveness and the ability to detect calcific subadventitial plaques, which are difficult to diagnose using conventional angiography. MDCT may be used as a safe and non-invasive method to assess RA and UA prior to harvesting the upper limb artery. Preoperative imaging of forehand arteries is a means to avoid unnecessary forearm

  13. CT angiography - arms and legs

    Science.gov (United States)

    Computed tomography angiography - peripheral; CTA - peripheral; CTA - Runoff ... be due to: Inflammation of the blood vessels Injury to the blood vessels Buerger disease (thromboangiitis obliterans) , ...

  14. [Contribution of computerized tomography in the diagnosis of cerebrovascular accidents in Nouakchott, Mauritania].

    Science.gov (United States)

    Diagana, M; Traore, H; Bassima, A; Druet-Cabanac, M; Preux, P M; Dumas, M

    2002-01-01

    This prospective study was focused on the radiological features of stroke and the recent contribution of computerized tomographic scan (CT scan) to diagnosis of hospitalized stroke patients. All patients admitted for stroke to the Neurology Department of the Nouakchott Hospital between January 1, 1996 and June 30, 1997 were enrolled in this study. Patients were divided into two groups, i.e. CT group including patients that underwent CT scan during hospitalization and control group including patients that did not undergo CT scan for financial reasons. The etiology of stroke (35.1% of hospitalizations) was ischemic in 52% of cases and hemorrhagic in 48%. There were more men than women and mean age was 60 years for ischemic stroke versus 56 years for hemorrhagic stroke. Only 8% of patients presented documented diabetes. Deep infarction accounted for 52% of ischemic stroke including large-artery infarction in 61.2% and lacunar infarction in 38.8%. Superficial infarction usually involved the territory supplied by the superficial sylvian artery. Intraparenchymal hematomas accounted for 78% of hemorrhagic strokes in relation with the high incidence of arterial hypertension (65.2%). The most common locations were capsulo-lenticular (55%) and capsulo-thalamic (39%). Stroke-related mortality was high (20.3%) especially in patients presenting prolonged disturbances of consciousness and renal insufficiency. By allowing more accurate assessment of lesions, CT-scan improved patient management and therapeutic outcome.

  15. Pre-Pulseless Takayasu's Arteritis Evaluated with 18F-FDG Positron Emission Tomography and Gadolinium-Enhanced Magnetic Resonance Angiography

    Science.gov (United States)

    Meave, Aloha; Soto, Maria E.; Reyes, Pedro A.; Cruz, Patricio; Talayero, Jose A.; Sierra, Carlos; Alexanderson, Erick

    2007-01-01

    Takayasu's arteritis is a primary vasculitis that affects large vessels and is characterized by chronic granulomatous inflammation. Diagnosis has been primarily clinical, with verification by angiography as the gold standard. More recently, however, it has become apparent that positron emission tomography enables better evaluation of vascular inflammation. This study presents 2 cases of Takayasu's arteritis. Magnetic resonance angiography was used to evaluate aortic anatomy by analyzing vascular wall thickness and also to quantify disease activity by measuring gadolinium enhancement. Positron emission tomography was used to evaluate active vascular inflammation by quantifying fluorodeoxyglucose F18 uptake. We conclude that both techniques support clinical diagnosis and aid in the evaluation of disease activity during and after treatment. PMID:18172533

  16. Method of evaluation of diagnostics reference levels in computerized tomography; Metodo de avaliacao de niveis de referencia de radiodiagnostico em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  17. Relative Hypodense Vertebral Artery Sign on Computerized Tomography in Atherosclerotic Near Occlusion

    Directory of Open Access Journals (Sweden)

    Muhammad Faraz Raghib

    2016-01-01

    Full Text Available A 52-year-old white male presented with an acute onset of slurred speech along with hypoesthesia in the entire left arm. The acute computed tomography (CT showed relative hypodensity in the intracranial segment of left vertebral artery (VA that was not present in historical images, pointing to the possible lack of flow. The site of occlusion was confirmed by magnetic resonance imaging (MRI that showed susceptibility effect in the affected artery. By means of historical native CT comparison the site of VA thrombosis was correctly predicted. Local atherosclerotic thrombosis of the VA could be relatively hypodense on native CT and still have positive susceptibility weighted imaging (SWI sign.

  18. Is the systematic use of automatic exposure monitoring justified in pediatrics abdomen computerized tomography?; L'utilisation systematique du controle automatique d'exposition est-elle justifiee en TDM abdominale pediatique?

    Energy Technology Data Exchange (ETDEWEB)

    Brisse, H.; Robilliard, M.; Pierrat, N.; Gaboriaud, G.; Neuenschwander, S.; Rosenwald, J.C.; Aubert, B

    2007-10-15

    The use of automatic exposure in pediatrics abdomen computerized tomography induces an increase and possibly useless of the dose to pelvic organs, and then must be justified for what diagnosis is expected from this medical examination. (N.C.)

  19. Virtual Reality Therapy for the Treatment of Alcohol Dependence: A Preliminary Investigation With Positron Emission Tomography/Computerized Tomography.

    Science.gov (United States)

    Son, Ji Hyun; Lee, Sang Hoon; Seok, Ju Won; Kee, Baik Seok; Lee, Hyun Woong; Kim, Hyung Joon; Lee, Tae Kyung; Han, Doug Hyun

    2015-07-01

    Virtual reality therapy (VRT) uses multimodal stimulation that includes visual, auditory, olfactory, and gustatory stimuli. The aim of this study was to assess the effectiveness of VRT in treating subjects with alcohol dependence (AD) by evaluating changes in brain metabolism. The VRT protocol consisted of three steps: relaxation, presentation of a high-risk situation, and presentation of an aversive situation. Twelve alcohol-dependent subjects underwent 10 sessions of VRT. The alcohol-dependent subjects were assessed with 18F-fluorodeoxyglucose positron emission tomography images before and after VRT, whereas the control group underwent imaging according to the same protocol only at baseline. Compared with the healthy control group, AD subjects showed higher metabolism in the right lentiform nucleus and right temporal lobe (BA20) at baseline (P(FDR brain metabolism in the right lentiform nucleus (P(FDR < .05) = .026) and right temporal lobe (BA38, P(FDR < .05) = .032) relative to that at baseline. Our results suggest a neurobiological imbalance, notably, a high sensitivity to stimuli, in the limbic system in subjects with AD. Furthermore, we determined that metabolism decreased in the basal ganglia after VRT, which may explain the limbic-regulated responses of reward and regulation. Therefore, we tentatively recommend VRT to treat AD through its regulating effect on limbic circuits.

  20. Dose profile study on computerized tomography scanning of skull with simulator object; Estudo do perfil de dose em varreduras de TC de cranio com objeto simulador

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, A.P., E-mail: aprata@des.cefetmg.b [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET/MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar; Alonso, Thessa C.; Silva, Teogenes A. da, E-mail: alonso@cdtn.b, E-mail: silvata@@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-10-26

    This work presents a comparison among the dose profiles in scanning of computerized tomography of a simulator object of PMMA in its periphery region. To obtain the deposited dose at the PMMA thermoluminescent dosemeters were used positioned at the interior of PMMA simulated object longitudinal to periphery and at the center of cylinder (positions denominated North, South, East, West and Center). Eight scanning were performed of simulator object using the routine protocol for skull in eight different services of radiodiagnostic by TC

  1. Reduced radiation exposure for face transplant surgical planning computed tomography angiography.

    Directory of Open Access Journals (Sweden)

    Kurt Schultz

    Full Text Available OBJECTIVE: To test the hypothesis that wide area detector face transplant surgical planning CT angiograms with simulated lower radiation dose and iterative reconstruction (AIDR3D are comparable in image quality to those with standard tube current and filtered back projection (FBP reconstruction. MATERIALS AND METHODS: The sinograms from 320-detector row CT angiography of four clinical candidates for face transplantation were processed utilizing standard FBP, FBP with simulated 75, 62, and 50% tube current, and AIDR3D with corresponding dose reduction. Signal-to-noise ratio (SNR and contrast-to-noise ratio (CNR were measured at muscle, fat, artery, and vein. Image quality for each reconstruction strategy was assessed by two independent readers using a 4-point scale. RESULTS: Compared to FBP, the median SNR and CNR for AIDR3D images were higher at all sites for all 4 different tube currents. The AIDR3D with simulated 50% tube current achieved comparable SNR and CNR to FBP with standard dose (median muscle SNR: 5.77 vs. 6.23; fat SNR: 6.40 vs. 5.75; artery SNR: 43.8 vs. 45.0; vein SNR: 54.9 vs. 55.7; artery CNR: 38.1 vs. 38.6; vein CNR: 49.0 vs. 48.7; all p-values >0.19. The interobserver agreement in the image quality score was good (weighted κ = 0.7. The overall score and the scores for smaller arteries were significantly lower when FBP with 50% dose reduction was used. The AIDR3D reconstruction images with 4 different simulated doses achieved a mean score ranging from 3.68 to 3.82 that were comparable to the scores from images reconstructed using FBP with original dose (3.68-3.77. CONCLUSIONS: Simulated radiation dose reduction applied to clinical CT angiography for face transplant planning suggests that AIDR3D allows for a 50% reduction in radiation dose, as compared to FBP, while preserving image quality.

  2. An Anatomical Study of Maxillary-Zygomatic Complex Using Three-Dimensional Computerized Tomography-Based Zygomatic Implantation

    Directory of Open Access Journals (Sweden)

    Xiangliang Xu

    2017-01-01

    Full Text Available Objective. To obtain anatomical data of maxillary-zygomatic complex based on simulating the zygomatic implantation using cadaver heads and three-dimensional computerized tomography (3D-CT. Methods. Simulating zygomatic implantation was performed using seven cadaver heads and 3D-CT images from forty-eight adults. After measuring the maxillary-zygomatic complex, we analyzed the position between the implantation path and the maxillary sinus cavity as well as the distance between the implantation path and the zygomatic nerve. Results. The distance from the starting point to the endpoint of the implant was 56.85 ± 5.35 mm in cadaver heads and 58.15 ± 7.37 mm in 3D-CT images. For the most common implantation path (80.20%, the implant went through the maxillary sinus cavity completely. The projecting points of the implant axis (IA on the surface of zygoma were mainly located in the region of frontal process of zygomatic bone close to the lateral orbital wall. The distances between IA and zygomatic nerve in 53 sides were shorter than 2 mm. Conclusion. The simulating zygomatic implantation on cadaver skulls and 3D-CT imaging provided useful anatomical data of the maxillary-zygomatic complex. It is necessary to take care to avoid the zygomatic nerve injury during implantation, because it frequently appears on the route of implantation.

  3. Multislice computerized tomography of the heart and coronary arteries; Exploration par tomodensitometrie multidetecteur du coeur et des arteres coronaires

    Energy Technology Data Exchange (ETDEWEB)

    Dacher, J.N.; Bertrand, D.; Belhiba, H. [Centre Hospitalier Universitaire, Service de Radiologie, Dept. d' Imagerie Medicale, LITIS EA 4108, Hopital Charles-Nicolle, 76 - Rouen (France); Tron, Ch. [Centre Hospitalier Universitaire, Service de Cardiologie, Hopital Charles-Nicolle, 76 - Rouen (France)

    2007-12-15

    Due to its excellent spatial and temporal resolution, multislice computerized tomography (M.S.C.T.) allows visualizing the heart and coronary arteries. Although the indications of M.S.C.T. did not reach a consensus level yet, some trends can be stated. The advantages and limitations of M.S.C.T. in cardiac exploration are summarized in this article. The indications are mainly based on the excellent negative predictive value of M.S.C.T. regarding coronary artery disease. Hence, patients at low to moderate risk of coronary artery disease (CAD) mostly benefit of the technique. M.S.C.T. can be an alternate examination in case of non feasible or non contributive stress test. M.S.C.T. is highly contributive in the ostial analysis, in detecting abnormal coronary implantation or course, in assessing a reimplanted artery or in analysing bypass grafts. M.S.C.T. remains limited in patients with heavily calcified coronary arteries, and in patients with stented distal arteries. (authors)

  4. Differentiation of oncocytoma and renal cell carcinoma in small renal masses (<4 cm): the role of 4-phase computerized tomography.

    Science.gov (United States)

    Bird, Vincent G; Kanagarajah, Prashanth; Morillo, Gaston; Caruso, Daniel J; Ayyathurai, Rajinikanth; Leveillee, Raymond; Jorda, Merce

    2011-12-01

    We investigate the use of 4-phase computerized tomography with intravenous contrast to help distinguish oncocytoma from renal cell carcinoma (RCC) in tumors renal tumors renal mass protocol and had confirmed pathological diagnosis of either oncocytoma or RCC were included in the study. Enhancement readings were obtained for the tumor and the renal cortex using the same slice simultaneously. Our cohort involved 69 patients (46 men, 23 women; mean age 66) who presented with 79 renal masses. Histopathologically 40 were clear cell, 22 papillary, 5 chromophobe RCC and 12 oncocytoma. On the arterial, venous and delayed phase images, oncocytoma showed the highest mean enhancement change, i.e.,546, 396 and 239% followed by clear cell RCC 261, 261 and 174%, chromophobe RCC 147, 127 and 66% and papillary RCC 137, 184 and 118%, respectively. The enhancement pattern differed significantly on comparing oncocytoma with RCC (P oncocytoma, respectively. The enhancement and washout values in Hounsfield units obtained by multiphasic CT scan aid in distinguishing oncocytoma from the commonly seen subtypes of RCC in renal masses renal oncocytomas.

  5. The application of compressive sampling in rapid ultrasonic computerized tomography (UCT) technique of steel tube slab (STS)

    Science.gov (United States)

    Jiang, Baofeng; Jia, Pengjiao; Zhao, Wen; Wang, Wentao

    2018-01-01

    This paper explores a new method for rapid structural damage inspection of steel tube slab (STS) structures along randomly measured paths based on a combination of compressive sampling (CS) and ultrasonic computerized tomography (UCT). In the measurement stage, using fewer randomly selected paths rather than the whole measurement net is proposed to detect the underlying damage of a concrete-filled steel tube. In the imaging stage, the ℓ1-minimization algorithm is employed to recover the information of the microstructures based on the measurement data related to the internal situation of the STS structure. A numerical concrete tube model, with the various level of damage, was studied to demonstrate the performance of the rapid UCT technique. Real-world concrete-filled steel tubes in the Shenyang Metro stations were detected using the proposed UCT technique in a CS framework. Both the numerical and experimental results show the rapid UCT technique has the capability of damage detection in an STS structure with a high level of accuracy and with fewer required measurements, which is more convenient and efficient than the traditional UCT technique. PMID:29293593

  6. The reliability of Cavalier's principle of stereological method in determining volumes of enchondromas using the computerized tomography tools.

    Science.gov (United States)

    Acar, Nihat; Karakasli, Ahmet; Karaarslan, Ahmet; Mas, Nermin Ng; Hapa, Onur

    2017-01-01

    Volumetric measurements of benign tumors enable surgeons to trace volume changes during follow-up periods. For a volumetric measurement technique to be applicable, it should be easy, rapid, and inexpensive and should carry a high interobserver reliability. We aimed to assess the interobserver reliability of a volumetric measurement technique using the Cavalier's principle of stereological methods. The computerized tomography (CT) of 15 patients with a histopathologically confirmed diagnosis of enchondroma with variant tumor sizes and localizations was retrospectively reviewed for interobserver reliability evaluation of the volumetric stereological measurement with the Cavalier's principle, V = t × [((SU) × d) /SL]2 × Σ P. The volumes of the 15 tumors collected by the observers are demonstrated in Table 1. There was no statistical significance between the first and second observers ( p = 0.000 and intraclass correlation coefficient = 0.970) and between the first and third observers ( p = 0.000 and intraclass correlation coefficient = 0.981). No statistical significance was detected between the second and third observers ( p = 0.000 and intraclass correlation coefficient = 0.976). The Cavalier's principle with the stereological technique using the CT scans is an easy, rapid, and inexpensive technique in volumetric evaluation of enchondromas with a trustable interobserver reliability.

  7. An Anatomical Study of Maxillary-Zygomatic Complex Using Three-Dimensional Computerized Tomography-Based Zygomatic Implantation.

    Science.gov (United States)

    Xu, Xiangliang; Zhao, Shijie; Liu, Hui; Sun, Zhipeng; Wang, Jianwei; Zhang, Weiguang

    2017-01-01

    To obtain anatomical data of maxillary-zygomatic complex based on simulating the zygomatic implantation using cadaver heads and three-dimensional computerized tomography (3D-CT). Simulating zygomatic implantation was performed using seven cadaver heads and 3D-CT images from forty-eight adults. After measuring the maxillary-zygomatic complex, we analyzed the position between the implantation path and the maxillary sinus cavity as well as the distance between the implantation path and the zygomatic nerve. The distance from the starting point to the endpoint of the implant was 56.85 ± 5.35 mm in cadaver heads and 58.15 ± 7.37 mm in 3D-CT images. For the most common implantation path (80.20%), the implant went through the maxillary sinus cavity completely. The projecting points of the implant axis (IA) on the surface of zygoma were mainly located in the region of frontal process of zygomatic bone close to the lateral orbital wall. The distances between IA and zygomatic nerve in 53 sides were shorter than 2 mm. The simulating zygomatic implantation on cadaver skulls and 3D-CT imaging provided useful anatomical data of the maxillary-zygomatic complex. It is necessary to take care to avoid the zygomatic nerve injury during implantation, because it frequently appears on the route of implantation.

  8. Detection accuracy of proximal caries by phosphor plate and cone-beam computerized tomography images scanned with different resolutions.

    Science.gov (United States)

    Cheng, Jun-Ge; Zhang, Zhi-Ling; Wang, Xiao-Yan; Zhang, Zu-Yan; Ma, Xu-Chen; Li, Gang

    2012-08-01

    This study was carried out to assess whether the spatial resolution has an impact on the detection accuracy of proximal caries in flat panel CBCT (cone beam computerized tomography) images and if the detection accuracy can be improved by flat panel CBCT images scanned with high spatial resolution when compared to digital intraoral images. The CBCT test images of 45 non-restored human permanent teeth were respectively scanned with the ProMax 3D and the DCT Pro scanners at different resolutions. Digital images were obtained with a phosphor plate imaging system Digora Optime. Eight observers evaluated all the test images for carious lesion within the 90 proximal surfaces. With the histological examination serving as the reference standard, observer performances were evaluated by receiver operating characteristic (ROC) curves. The areas under the ROC curves were analyzed with two-way analysis of variance. No significant differences were found among the CBCT images and between CBCT and digital images when only proximal enamel caries was detected (p = 0.989). With respect to the detection of proximal dentinal caries, significant difference was found between CBCT and digital images (p proximal caries in flat panel CBCT images. The flat panel CBCT images scanned with high spatial resolution did not improve the detection accuracy of proximal enamel caries compared to digital intraoral images. CBCT images scanned with high spatial resolutions could not be used for proximal caries detection.

  9. Optimizing computed tomography pulmonary angiography using right atrium bolus monitoring combined with spontaneous respiration

    Energy Technology Data Exchange (ETDEWEB)

    Min, Wang; Jian, Li; Rui, Zhai [Jining No. 1 People' s Hospital, Department of Computed Tomography, Jining City, ShanDong Province (China); Wen, Li [Jining No. 1 People' s Hospital, Department of Gastroenterology, Jining, ShanDong (China); Dai, Lun-Hou [Shandong Chest Hospital, Department of Radiology, Jinan, ShanDong (China)

    2015-09-15

    CT pulmonary angiography (CTPA) aims to provide pulmonary arterial opacification in the absence of significant pulmonary venous filling. This requires accurate timing of the imaging acquisition to ensure synchronization with the peak pulmonary artery contrast concentration. This study was designed to test the utility of right atrium (RA) monitoring in ensuring optimal timing of CTPA acquisition. Sixty patients referred for CTPA were divided into two groups. Group A (n = 30): CTPA was performed using bolus triggering from the pulmonary trunk, suspended respiration and 70 ml of contrast agent (CA). Group B (n = 30): CTPA image acquisition was triggered using RA monitoring with spontaneous respiration and 40 ml of CA. Image quality was compared. Subjective image quality, average CT values of pulmonary arteries and density difference between artery and vein pairs were significantly higher whereas CT values of pulmonary veins were significantly lower in group B (all P < 0.05). There was no significant difference between the groups in the proportion of subjects where sixth grade pulmonary arteries were opacified (P > 0.05). RA monitoring combined with spontaneous respiration to trigger image acquisition in CTPA produces optimal contrast enhancement in pulmonary arterial structures with minimal venous filling even with reduced doses of CA. (orig.)

  10. The comparison of bolus tracking and test bolus techniques for computed tomography thoracic angiography in healthy beagles

    Directory of Open Access Journals (Sweden)

    Nicolette Cassel

    2013-02-01

    Full Text Available Computed tomography thoracic angiography studies were performed on five adult beagles using the bolus tracking (BT technique and the test bolus (TB technique, which were performed at least two weeks apart. For the BT technique, 2 mL/kg of 300 mgI/mL iodinated contrast agent was injected intravenously. Scans were initiated when the contrast in the aorta reached 150 Hounsfield units (HU. For the TB technique, the dogs received a test dose of 15% of 2 mL/kg of 300 mgI/mL iodinated contrast agent, followed by a series of low dose sequential scans. The full dose of the contrast agent was then administered and the scans were conducted at optimal times as identified from time attenuation curves. Mean attenuation in HU was measured in the aorta (Ao and right caudal pulmonary artery (rCPA. Additional observations included the study duration, milliAmpere (mA, computed tomography dose index volume (CTDI[vol] and dose length product (DLP. The attenuation in the Ao (BT = 660 52 HU ± 138 49 HU, TB = 469 82 HU ± 199 52 HU, p = 0.13 and in the rCPA (BT = 606 34 HU ± 143 37 HU, TB = 413 72 HU ± 174.99 HU, p = 0.28 did not differ significantly between the two techniques. The BT technique was conducted in a significantly shorter time period than the TB technique (p = 0.03. The mean mA for the BT technique was significantly lower than the TB technique (p = 0.03, as was the mean CTDI(vol (p = 0.001. The mean DLP did not differ significantly between the two techniques (p = 0.17. No preference was given to either technique when evaluating the Ao or rCPA but the BT technique was shown to be shorter in duration and resulted in less DLP than the TB technique.

  11. The comparison of bolus tracking and test bolus techniques for computed tomography thoracic angiography in healthy beagles

    Directory of Open Access Journals (Sweden)

    Nicolette Cassel

    2013-05-01

    Full Text Available Computed tomography thoracic angiography studies were performed on five adult beagles using the bolus tracking (BT technique and the test bolus (TB technique, which were performed at least two weeks apart. For the BT technique, 2 mL/kg of 300 mgI/mL iodinated contrast agent was injected intravenously. Scans were initiated when the contrast in the aorta reached 150 Hounsfield units (HU. For the TB technique, the dogs received a test dose of 15% of 2 mL/kg of 300 mgI/mL iodinated contrast agent, followed by a series of low dose sequential scans. The full dose of the contrast agent was then administered and the scans were conducted at optimal times as identified from time attenuation curves. Mean attenuation in HU was measured in the aorta (Ao and right caudal pulmonary artery (rCPA. Additional observations included the study duration, milliAmpere (mA, computed tomography dose index volume (CTDI[vol] and dose length product (DLP. The attenuation in the Ao (BT = 660 52 HU ± 138 49 HU, TB = 469 82 HU ± 199 52 HU, p = 0.13 and in the rCPA (BT = 606 34 HU ± 143 37 HU, TB = 413 72 HU ± 174.99 HU, p = 0.28 did not differ significantly between the two techniques. The BT technique was conducted in a significantly shorter time period than the TB technique (p = 0.03. The mean mA for the BT technique was significantly lower than the TB technique (p = 0.03, as was the mean CTDI(vol (p = 0.001. The mean DLP did not differ significantly between the two techniques (p = 0.17. No preference was given to either technique when evaluating the Ao or rCPA but the BT technique was shown to be shorter in duration and resulted in less DLP than the TB technique.

  12. Image quality in low-dose coronary computed tomography angiography with a new high-definition CT scanner.

    Science.gov (United States)

    Kazakauskaite, Egle; Husmann, Lars; Stehli, Julia; Fuchs, Tobias; Fiechter, Michael; Klaeser, Bernd; Ghadri, Jelena R; Gebhard, Catherine; Gaemperli, Oliver; Kaufmann, Philipp A

    2013-02-01

    A new generation of high definition computed tomography (HDCT) 64-slice devices complemented by a new iterative image reconstruction algorithm-adaptive statistical iterative reconstruction, offer substantially higher resolution compared to standard definition CT (SDCT) scanners. As high resolution confers higher noise we have compared image quality and radiation dose of coronary computed tomography angiography (CCTA) from HDCT versus SDCT. Consecutive patients (n = 93) underwent HDCT, and were compared to 93 patients who had previously undergone CCTA with SDCT matched for heart rate (HR), HR variability and body mass index (BMI). Tube voltage and current were adapted to the patient's BMI, using identical protocols in both groups. The image quality of all CCTA scans was evaluated by two independent readers in all coronary segments using a 4-point scale (1, excellent image quality; 2, blurring of the vessel wall; 3, image with artefacts but evaluative; 4, non-evaluative). Effective radiation dose was calculated from DLP multiplied by a conversion factor (0.014 mSv/mGy × cm). The mean image quality score from HDCT versus SDCT was comparable (2.02 ± 0.68 vs. 2.00 ± 0.76). Mean effective radiation dose did not significantly differ between HDCT (1.7 ± 0.6 mSv, range 1.0-3.7 mSv) and SDCT (1.9 ± 0.8 mSv, range 0.8-5.5 mSv; P = n.s.). HDCT scanners allow low-dose 64-slice CCTA scanning with higher resolution than SDCT but maintained image quality and equally low radiation dose. Whether this will translate into higher accuracy of HDCT for CAD detection remains to be evaluated.

  13. Comparison of Optical Coherence Tomography Angiography and Laser Speckle Flowgraphy for the Diagnosis of Normal-Tension Glaucoma

    Directory of Open Access Journals (Sweden)

    Asuka Takeyama

    2018-01-01

    Full Text Available Purpose. To compare optical coherence tomography angiography (OCT-A and laser speckle flowgraphy (LSFG for the diagnosis of normal-tension glaucoma (NTG. Methods. Twenty-eight eyes of 28 patients with NTG and 25 eyes of 25 normal subjects matched for age, refractive errors, systemic blood pressure, and central corneal thickness were evaluated. OCT-A was used to measure whole image vessel density, inside disc vessel density, and peripapillary vessel density; using LSFG, mean blur rate (MBR inside the whole optic nerve head (ONH area (MBRA, and MBR of the vessel area (MBRV and tissue area (MBRT inside the ONH, were determined. Receiver operating characteristic (ROC curves and areas under the ROC (AUROC were used to assess the diagnostic ability of each variable. Results. The AUROC for OCT-A whole image vessel density (0.950 was significantly greater than that for OCT-A peripapillary vessel density (0.830 and for all LSFG parameters (MBRA = 0.793, MBRV = 0.601, and MBRT = 0.61 (P<0.001. The AUROC for OCT-A inside disc vessel density (0.931 was significantly greater than that for all LSFG parameters (P<0.005. Conclusions. OCT-A vessel density had a higher glaucoma diagnostic ability compared to all LSFG parameters in patients with NTG.

  14. The proper use of coronary calcium score and coronary computed tomography angiography for screening asymptomatic patients with cardiovascular risk factors.

    Science.gov (United States)

    Tay, Shee Yen; Chang, Po-Yen; Lao, Wilson T; Lin, Ying Chin; Chung, Yi-Han; Chan, Wing P

    2017-12-15

    Early detection and treatment of coronary artery disease (CAD) can reduce incidences of acute myocardial infarction. In this study, we determined the proper use of contributing risk factors and coronary artery calcium score (CACS) when screening asymptomatic patients with coronary arterial stenoses using coronary computed tomography angiography (CCTA). We reviewed 934 consecutive patients who received CACS and CCTA between December 2013 and November 2016. At least one cardiovascular disease risk factor was present in each of the 509 asymptomatic participants. Patients were grouped based on CACS into "zero," "minimal" (0  400). Males over 45 years old with diabetes mellitus and hypertension had a higher risk of significant coronary stenosis. In multivariate analysis, age, sex, hypertension, and diabetes mellitus remained significant predictors of stenosis. A CACS of zero occurred in 227 patients (44.6%). There were no significant differences between the "zero" and "minimal" groups (p = 0.421), but the "mild," "moderate," and "excessive" groups showed correlations with significant coronary stenosis. Age, sex, diabetes mellitus, and hypertension were associated with higher risk of significant coronary stenosis. Asymptomatic patients with CACSs of zero do not require CCTA, and thereby avoid unnecessary radiation exposure.

  15. Adaptive Statistical Iterative Reconstruction-V: Impact on Image Quality in Ultralow-Dose Coronary Computed Tomography Angiography.

    Science.gov (United States)

    Benz, Dominik C; Gräni, Christoph; Mikulicic, Fran; Vontobel, Jan; Fuchs, Tobias A; Possner, Mathias; Clerc, Olivier F; Stehli, Julia; Gaemperli, Oliver; Pazhenkottil, Aju P; Buechel, Ronny R; Kaufmann, Philipp A

    The clinical utility of a latest generation iterative reconstruction algorithm (adaptive statistical iterative reconstruction [ASiR-V]) has yet to be elucidated for coronary computed tomography angiography (CCTA). This study evaluates the impact of ASiR-V on signal, noise and image quality in CCTA. Sixty-five patients underwent clinically indicated CCTA on a 256-slice CT scanner using an ultralow-dose protocol. Data sets from each patient were reconstructed at 6 different levels of ASiR-V. Signal intensity was measured by placing a region of interest in the aortic root, LMA, and RCA. Similarly, noise was measured in the aortic root. Image quality was visually assessed by 2 readers. Median radiation dose was 0.49 mSv. Image noise decreased with increasing levels of ASiR-V resulting in a significant increase in signal-to-noise ratio in the RCA and LMA (P ASiR-V (P ASiR-V yields substantial noise reduction and improved image quality enabling introduction of ultralow-dose CCTA.

  16. Long-term prognostic performance of low-dose coronary computed tomography angiography with prospective electrocardiogram triggering

    Energy Technology Data Exchange (ETDEWEB)

    Clerc, Olivier F.; Kaufmann, Basil P.; Possner, Mathias; Liga, Riccardo; Vontobel, Jan; Mikulicic, Fran; Graeni, Christoph; Benz, Dominik C.; Fuchs, Tobias A.; Stehli, Julia; Pazhenkottil, Aju P.; Gaemperli, Oliver; Kaufmann, Philipp A.; Buechel, Ronny R. [University Hospital Zurich, Cardiac Imaging, Department of Nuclear Medicine, Zurich (Switzerland)

    2017-11-15

    To assess long-term prognosis after low-dose 64-slice coronary computed tomography angiography (CCTA) using prospective electrocardiogram-triggering. We included 434 consecutive patients with suspected or known coronary artery disease referred for low-dose CCTA. Patients were classified as normal, with non-obstructive or obstructive lesions, or previously revascularized. Coronary artery calcium score (CACS) was assessed in 223 patients. Follow-up was obtained regarding major adverse cardiac events (MACE): cardiac death, myocardial infarction and elective revascularization. We performed Kaplan-Meier analysis and Cox regressions. Mean effective radiation dose was 1.7 ± 0.6 mSv. At baseline, 38% of patients had normal arteries, 21% non-obstructive lesions, 32% obstructive stenosis and 8% were revascularized. Twenty-nine patients (7%) were lost to follow-up. After a median follow-up of 6.1 ± 0.6 years, MACE occurred in 0% of patients with normal arteries, 6% with non-obstructive lesions, 30% with obstructive stenosis and 39% of those revascularized. MACE occurrence increased with increasing CACS (P < 0.001), but 4% of patients with CACS = 0 experienced MACE. Multivariate Cox regression identified obstructive stenosis, lesion burden in CCTA and CACS as independent MACE predictors (P ≤ 0.001). Low-dose CCTA with prospective electrocardiogram-triggering has an excellent long-term prognostic performance with a warranty period >6 years for patients with normal coronary arteries. (orig.)

  17. [Optical Coherence Tomography Angiography in Diagnosis and Post-Treatment Assessment of Hemangioblastomas in Hippel-Lindau Disease].

    Science.gov (United States)

    Lang, S J; Evers, C; Cakir, B; Ludwig, F; Lange, C; Agostini, H

    2017-09-01

    Background Optical coherence tomography angiography (OCTA) offers the possibility to visualize, non-invasively, blood vessels of the retina. In vascular tumors, especially hemangioblastomas in Hippel-Lindau disease, new information can be obtained with OCTA concerning structure of the tumor, tumor activity and treatment success. Patients Ten eyes of 10 patients with retinal hemangioblastoma in Hippel-Lindau disease were included. The age of the patients ranged from 19 years to 65 years (median 44 years). Results A total of 10 active and one inactive hemangioblastomas were examined with OCTA. In larger tumors, only the superficial blood flow could be visualized. Four hemangioblastomas were not treated due to their location near the optic nerve head. Six hemangioblastomas in the peripheral retina were treated with laser photocoagulation. In 4 eyes, a reduced blood flow could be shown directly after the treatment. The visualization of the perfusion was partially blocked after laser treatment. Conclusion OCTA enables innovative methods of pre- and postoperative assessment of retinal hemangioblastomas. It has the potential to give new information about the morphology, activity and effects of treatment. Prospective studies with longer follow-up are needed to evaluate the therapeutic relevance of this new imaging method. Georg Thieme Verlag KG Stuttgart · New York.

  18. Optical Coherence Tomography Angiography of the Superficial Microvasculature in the Macular and Peripapillary Areas in Glaucomatous and Healthy Eyes.

    Science.gov (United States)

    Chen, Henry Shen-Lih; Liu, Chun-Hsiu; Wu, Wei-Chi; Tseng, Hsiao-Jung; Lee, Yung-Sung

    2017-07-01

    To quantitatively evaluate the superficial microvasculature in the macular and peripapillary areas in glaucomatous and healthy eyes using optical coherence tomography angiography (OCT-A). We enrolled 26 eyes of medically managed primary open-angle glaucoma patients and 27 eyes of healthy subjects were enrolled in this prospective study. Measurements of OCT-A vessel density were acquired both in the macular and peripapillary areas. We compared vessel density values, the circumpapillary retinal nerve fiber layer (cpRNFL), the ganglion cell complex (GCC), and standard automated perimetry (SAP) parameters across study groups. Areas under the receiver operating characteristic (AUROC) curves were used to evaluate diagnostic accuracy. Quadratic regression models were used to determine the correlations between SAP severity and outcome measures. The whole image vessel density (wiVD) in glaucomatous eyes was lower than that in healthy eyes in the macular (38.5% ± 2.2% vs. 43.2% ± 2.3%, P microvasculature in the macular area than do healthy eyes. The measurement of the macular superficial vessel density had similar diagnostic accuracy to peripapillary RNFL and macular GCC thickness for differentiating between glaucomatous and healthy eyes.

  19. Reproducibility and repeatability of foveal avascular zone area measurements using swept-source optical coherence tomography angiography in healthy subjects.

    Science.gov (United States)

    Mastropasqua, Rodolfo; Toto, Lisa; Mattei, Peter A; Di Nicola, Marta; Zecca, Isaia A L; Carpineto, Paolo; Di Antonio, Luca

    2017-05-11

    To assess the reproducibility and repeatability of foveal avascular zone (FAZ) area measurements using swept-source optical coherence tomography angiography (SS-OCTA) in healthy subjects. Sixty-four eyes of 64 healthy volunteers were randomly subjected to FAZ area measurements using SS-OCTA by 2 examiners in 2 different sessions. The FAZ areas measured by the first and second observer were 0.269 ± 0.092 mm2 and 0.270 ± 0.090 mm2, respectively. Within subjects, the coefficients of variations were 2.44% (95% confidence interval [CI] 1.95% to 2.93%) and 2.66% (95% CI 2.00% to 3.31%) for the first and second observers, respectively. The coefficient of repeatability average measurements of FAZ area were 0.021 mm2 and 0.024 mm2. The intraclass correlation coefficient values were 0.993 (95% CI 0.989 to 0.996) and 0.991 (95% CI 0.986 to 0.995). Interobserver and intraobserver concordance correlation coefficients ranged from 0.998 (95% CI 0.997 to 0.999) to 0.999 (95% CI 0.998 to 0.999) and from 0.989 (95% CI 0.982 to 0.993) to 0.987 (95% CI 0.979 to 0.992), respectively. The FAZ area measurements by means of SS-OCTA showed high reproducibility and repeatability in healthy eyes.

  20. Automatic motion correction for in vivo human skin optical coherence tomography angiography through combined rigid and nonrigid registration

    Science.gov (United States)

    Wei, David Wei; Deegan, Anthony J.; Wang, Ruikang K.

    2017-06-01

    When using optical coherence tomography angiography (OCTA), the development of artifacts due to involuntary movements can severely compromise the visualization and subsequent quantitation of tissue microvasculatures. To correct such an occurrence, we propose a motion compensation method to eliminate artifacts from human skin OCTA by means of step-by-step rigid affine registration, rigid subpixel registration, and nonrigid B-spline registration. To accommodate this remedial process, OCTA is conducted using two matching all-depth volume scans. Affine transformation is first performed on the large vessels of the deep reticular dermis, and then the resulting affine parameters are applied to all-depth vasculatures with a further subpixel registration to refine the alignment between superficial smaller vessels. Finally, the coregistration of both volumes is carried out to result in the final artifact-free composite image via an algorithm based upon cubic B-spline free-form deformation. We demonstrate that the proposed method can provide a considerable improvement to the final en face OCTA images with substantial artifact removal. In addition, the correlation coefficients and peak signal-to-noise ratios of the corrected images are evaluated and compared with those of the original images, further validating the effectiveness of the proposed method. We expect that the proposed method can be useful in improving qualitative and quantitative assessment of the OCTA images of scanned tissue beds.

  1. Prognostic value of incidental hypervascular micronodules detected on cone-beam computed tomography angiography of patients with liver metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Odisio, Bruno C.; Mahvash, Armeen; Gupta, Sanjay; Tam, Alda L.; Murthy, Ravi [The University of Texas MD Anderson Cancer Center, Department of Interventional Radiology, Division of Diagnostic Imaging, Houston, TX (United States); Cox, Veronica L.; Faria, Silvana C. [The University of Texas MD Anderson Cancer Center, Diagnostic Radiology, Houston, TX (United States); Yamashita, Suguru; Vauthey, Jean-Nicolas [The University of Texas MD Anderson Cancer Center, Surgical Oncology, Houston, TX (United States); Shi, Xiao [Baylor College of Medicine, Department of Diagnostic Radiology, Houston, TX (United States); Ensor, Joe [Biostatistics of the Houston Methodist Cancer Center, Houston, TX (United States); Jones, Aaron K. [The University of Texas MD Anderson Cancer Center, Imaging Physics, Houston, TX (United States)

    2017-11-15

    To determine the clinical relevance of incidentally-found hypervascular micronodules (IHM) on cone-beam computed tomography angiography (CBCTA) in patients with liver metastasis undergoing transarterial (chemo)embolization (TACE/TAE). This was a HIPAA-compliant institutional review board-approved single-institution retrospective review of 95 non-cirrhotic patients (52 men; mean age, 60 years) who underwent CBCTA prior to (chemo)embolic delivery. IHM were defined by the presence of innumerable subcentimetre hepatic parenchymal hypevascular foci not detected on pre-TACE/TAE contrast-enhanced cross-sectional imaging. Multivariate analysis was performed to compare time to tumour progression (TTP) between patients with and without IHM. IHM were present in 21 (22%) patients. Patients with IHM had a significantly shorter intrahepatic TTP determined by a higher frequency of developing new liver metastasis (hazard ratio [HR]: 1.99; 95% confidence interval [CI] 1.08-3.67, P= 0.02). Patients with IHM trended towards a shorter TTP of the tumour(s) treated with TACE/TAE (HR: 1.72; 95% CI: 0.98-3.01, P= 0.056). Extrahepatic TTP was not significantly different between the two cohorts (P= 0.27). Patients with IHM on CBCTA have worse prognosis due to a significantly higher risk of developing new hepatic tumours. Further work is needed to elucidate its underlying mechanisms of pathogenesis. (orig.)

  2. Effect of reader experience on variability, evaluation time and accuracy of coronary plaque detection with computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saur, Stefan C.; Szekely, Gabor [ETH Zurich, Computer Vision Laboratory, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Group, Boston, MA (United States); Stolzmann, Paul; Baumueller, Stephan; Leschka, Sebastian; Scheffel, Hans; Desbiolles, Lotus [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Fuchs, Thomas J. [ETH Zurich, Department of Computer Science, Zurich (Switzerland); Cattin, Philippe C. [ETH Zurich, Computer Vision Laboratory, Zurich (Switzerland); University of Basel, Medical Image Analysis Center, Basel (Switzerland)

    2010-07-15

    To assess the effect of reader experience on variability, evaluation time and accuracy in the detection of coronary artery plaques with computed tomography coronary angiography (CTCA). Three independent, blinded readers with three different experience levels twice labelled 50 retrospectively electrocardiography (ECG)-gated contrast-enhanced dual-source CTCA data sets (15 female, age 67.3 {+-} 10.4 years, range 46-86 years) indicating the presence or absence of coronary plaques. The evaluation times for the readings were recorded. Intra- and interobserver variability expressed as {kappa} statistics and sensitivity, specificity, and negative and positive predictive values were calculated for plaque detection, with a consensus reading of the three readers taken as the standard of reference. A bootstrap method was applied in the statistical analysis to account for clustering. Significant correlations were found between reader experience and, respectively, evaluation times (r = -0.59, p < 0.05) and intraobserver variability (r = 0.73, p < 0.05). The evaluation time significantly differed among the readers (p < 0.05). The observer variability for plaque detection, compared with the consensus, varied between {kappa} = 0.582 and {kappa} = 0.802. Variability of plaque detection was significantly smaller (p < 0.05) and more accurate (p < 0.05) for the most experienced reader. Reader experience significantly correlated with observer variability, evaluation time and accuracy of coronary plaque detection at CTCA. (orig.)

  3. Optical coherence tomography angiography discerns preclinical diabetic retinopathy in eyes of patients with type 2 diabetes without clinical diabetic retinopathy.

    Science.gov (United States)

    Cao, Dan; Yang, Dawei; Huang, Zhongning; Zeng, Yunkao; Wang, Jun; Hu, Yunyan; Zhang, Liang

    2018-02-16

    To investigate changes in retinal vascular plexuses and choriocapillaris in patients with type 2 diabetes mellitus (DM2) without diabetic retinopathy (DR) and healthy controls using optical coherence tomography angiography (OCTA). A total of 71 DM2 and 67 healthy control subjects were included. All subjects underwent OCTA examination (RTVue-XR Avanti; Optovue, Fremont, CA, USA). Average vessel density in superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris, parafoveal vessel density in SCP and DCP, FAZ area (mm 2 ) in SCP, microaneurysms and capillary nonperfusion were taken into analysis. Parafoveal vessel density in both SCP and DCP decreased in the eyes without clinical DR compared to normal controls (p Diabetic patients with no signs of DR also had a significant reduction in average vessel density of SCP, DCP and choriocapillaris (p diabetic eyes, and capillary nonperfusion was noted in 18 of 71 diabetic eyes. We demonstrated that OCTA can identify preclinical DR before the manifestation of clinically apparent retinopathy in diabetic eyes. DM2 patients without DR have SCP, DCP and choriocapillaris impairment. Our results suggested that OCTA might be a promising tool for regular screening of diabetic eyes for DR.

  4. Age-related incidence of pulmonary embolism and additional pathologic findings detected by computed tomography pulmonary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Groth, M., E-mail: groth.michael@googlemail.com [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Henes, F.O., E-mail: f.henes@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Mayer, U., E-mail: mayer@uke.uni-hamburg.de [Emergency Department, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Regier, M., E-mail: m.regier@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Adam, G., E-mail: g.adam@uke.uni-hamburg.de [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Begemann, P.G.C., E-mail: p.begemann@me.com [Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2012-08-15

    Objective: To compare the incidence of pulmonary embolism (PE) and additional pathologic findings (APF) detected by computed tomography pulmonary angiography (CTPA) according to different age-groups. Materials and methods: 1353 consecutive CTPA cases for suspected PE were retrospectively reviewed. Patients were divided into seven age groups: {<=}29, 30-39, 40-49, 50-59, 60-69, 70-79 and {>=}80 years. Differences between the groups were tested using Fisher's exact or chi-square test. A p-value < 0.0024 indicated statistical significance when Bonferroni correction was used. Results: Incidence rates of PE ranged from 11.4% to 25.4% in different age groups. The three main APF were pleural effusion, pneumonia and pulmonary nodules. No significant difference was found between the incidences of PE in different age groups. Furthermore, APF in different age groups revealed no significant differences (all p-values > 0.0024). Conclusion: The incidences of PE and APF detected by CTPA reveal no significant differences between various age groups.

  5. Coronary computed tomography angiography - tolerability of β-blockers and contrast media, and temporal changes in radiation dose.

    Science.gov (United States)

    Pedersen, Charlotte; Thomsen, Camilla F; Hosbond, Susanne E; Thomassen, Anders; Mickley, Hans; Diederichsen, Axel C P

    2014-10-01

    To determine the risk in administering β-blockers, contrast-induced nephropathy (CIN) and the trend in X-ray use, during coronary computed tomography angiography (CCTA). A total of 416 patients were referred for elective CCTA. To achieve a resting heart rate below 60 beats per minute, oral and/or intravenous β-blockers were administered. Using questionnaires, information on the adverse effects of β-blockers was collected from the patients. The levels of s-creatinine and estimated GFR (eGFR) were measured before and after contrast enhanced CCTA. Radiation exposure was compared with the exposure 3 years earlier. There was no significant difference in the symptoms (dizziness, lipothymia and palpitations) between patients with and patients without β-blocker pretreatment. Compared to baseline values, the decrease in s-creatinine was not significant (75.2 vs. 74.6 μmol/L, p = 0.09), while the increase in eGFR was not significant (78 vs. 79 mL/min, p = 0.17). Also, subgroups of patients with hypertension, hypercholesterolemia, diabetes or pre-existing slight impairment in renal function did not develop CIN. The mean radiation exposure decreased from 17.5 to 6.7 mSv, p < 0.0001. In terms of the side effects of β-blockers and contrast media, there were no short term complications to CCTA. Furthermore, the radiation dose has been dramatically diminished over the last three years.

  6. The effect of blood pressure on non-invasive fractional flow reserve derived from coronary computed tomography angiography.

    Science.gov (United States)

    Kurata, Akira; Coenen, Adriaan; Lubbers, Marisa M; Nieman, Koen; Kido, Teruhito; Kido, Tomoyuki; Yamashita, Natsumi; Watanabe, Kouki; Krestin, Gabriel P; Mochizuki, Teruhito

    2017-04-01

    The aim of this study is to assess the effect of blood pressure (BP) on coronary computed tomography angiography (CTA) derived computational fractional flow reserve (CTA-FFR). Twenty-one patients who underwent coronary CTA and invasive FFR were retrospectively identified. Ischemia was defined as invasive FFR ≤0.80. Using a work-in-progress computational fluid dynamics algorithm, CTA-FFR was computed with BP measured before CTA, and simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg respectively. Correlation between CTA-FFR and invasive FFR was assessed using Pearson test. The repeated measuring test was used for multiple comparisons of CTA-FFR values by simulated BP inputs. Twenty-nine vessels (14 with invasive FFR ≤0.80) were assessed. The average CTA-FFR for measured BP (134 ± 20/73 ± 12 mmHg) was 0.77 ± 0.12. Correlation between CTA-FFR by measured BP and invasive FFR was good (r = 0.735, P blood pressure (BP) affects the CTA-FFR computation. • Measured BP before CT examination is preferable for accurate CTA-FFR simulation. • Inaccurate BP assumptions can cause misinterpretation of borderline significant lesions.

  7. Quantitative assessment on coronary computed tomography angiography (CCTA) image quality: comparisons between genders and different tube voltage settings.

    Science.gov (United States)

    Chian, Teo Chee; Nassir, Norziana Mat; Ibrahim, Mohd Izuan; Yusof, Ahmad Khairuddin Md; Sabarudin, Akmal

    2017-02-01

    This study was carried out to quantify and compare the quantitative image quality of coronary computed tomography angiography (CCTA) between genders as well as between different tube voltages scan protocols. Fifty-five cases of CCTA were collected retrospectively and all images including reformatted axial images at systolic and diastolic phases as well as images with curved multi planar reformation (cMPR) were obtained. Quantitative image quality including signal intensity, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of right coronary artery (RCA), left anterior descending artery (LAD), left circumflex artery (LCx) and left main artery (LM) were quantified using Analyze 12.0 software. Six hundred and fifty-seven coronary arteries were evaluated. There were no significant differences in any quantitative image quality parameters between genders. 100 kilovoltage peak (kVp) scanning protocol produced images with significantly higher signal intensity compared to 120 kVp scanning protocol (Pgenders and different tube voltages. Lower tube voltage (100 kVp) scanning protocol is recommended in clinical practice to reduce the radiation dose to patient.

  8. A comparison between ultrasonography and mammography, computed tomography and digital subtraction angiography for the detection of breast cancers

    Energy Technology Data Exchange (ETDEWEB)

    Tohnosu, Noriyuki; Okuyama, Kazuaki; Koide, Yoshio (Chiba Univ. (Japan). School of Medicine) (and others)

    1993-08-01

    Ultrasound (US) was compared with mammography (MMG), computed tomography (CT), and digital subtraction angiography (DSA) in its effectiveness to detect breast cancer masses and metastatic axillary nodes. Forty-seven breast cancer patients who all underwent MMG, US, CT, and DSA preoperatively in our institution between 1986 and 1990 were studied. US was able to detect tumors in all cases regardless of tumor size, whereas DSA detected T1-size tumors and MMG detected T2-size tumors in 40% and 64.7% of cases, respectively, being specifically inferior to US. It was found that MMG was least likely to detect papillotubular carcinoma, although microcalcification alone without a tumor mass on MMG improved detectability from 46.2% to 76.9%, according to the histological type. CT was found to be most sensitive to axillary node metastases (81.8%), followed by US (72.7%), but DSA was significantly unfavorable (42.9%). Thus, we concluded that US was superior to MMG, CT, and DSA for detecting breast cancer masses, but that CT was more advantageous than US, while DSA was of little value for evaluating axillary nodal status. (author).

  9. Clinical feasibility of 3D automated coronary atherosclerotic plaque quantification algorithm on coronary computed tomography angiography: Comparison with intravascular ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyung-Bok [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); Myongji Hospital, Division of Cardiology, Cardiovascular Center, Goyang (Korea, Republic of); Lee, Byoung Kwon [Yonsei University College of Medicine, Division of Cardiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Shin, Sanghoon [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); National Health Insurance Corporation Ilsan Hospital, Division of Cardiology, Goyang (Korea, Republic of); Heo, Ran; Chang, Hyuk-Jae; Chung, Namsik [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); Yonsei University Health System, Division of Cardiology, Severance Cardiovascular Hospital, Seoul (Korea, Republic of); Arsanjani, Reza [Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Cedars-Sinai Heart Institute, Los Angeles, CA (United States); Kitslaar, Pieter H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical Imaging Systems B.V., Leiden (Netherlands); Broersen, Alexander; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Ahn, Sung Gyun [Yonsei University Wonju Severance Christian Hospital, Division of Cardiology, Wonju (Korea, Republic of); Min, James K. [New York-Presbyterian Hospital, Institute for Cardiovascular Imaging, Weill-Cornell Medical College, New York, NY (United States); Hong, Myeong-Ki; Jang, Yangsoo [Yonsei University Health System, Division of Cardiology, Severance Cardiovascular Hospital, Seoul (Korea, Republic of)

    2015-10-15

    To evaluate the diagnostic performance of automated coronary atherosclerotic plaque quantification (QCT) by different users (expert/non-expert/automatic). One hundred fifty coronary artery segments from 142 patients who underwent coronary computed tomography angiography (CCTA) and intravascular ultrasound (IVUS) were analyzed. Minimal lumen area (MLA), maximal lumen area stenosis percentage (%AS), mean plaque burden percentage (%PB), and plaque volume were measured semi-automatically by expert, non-expert, and fully automatic QCT analyses, and then compared to IVUS. Between IVUS and expert QCT analysis, the correlation coefficients (r) for the MLA, %AS, %PB, and plaque volume were excellent: 0.89 (p < 0.001), 0.84 (p < 0.001), 0.91 (p < 0.001), and 0.94 (p < 0.001), respectively. There were no significant differences in the mean parameters (all p values >0.05) except %AS (p = 0.01). The automatic QCT analysis showed comparable performance to non-expert QCT analysis, showing correlation coefficients (r) of the MLA (0.80 vs. 0.82), %AS (0.82 vs. 0.80), %PB (0.84 vs. 0.73), and plaque volume (0.84 vs. 0.79) when they were compared to IVUS, respectively. Fully automatic QCT analysis showed clinical utility compared with IVUS, as well as a compelling performance when compared with semiautomatic analyses. (orig.)

  10. Microscope-Integrated Optical Coherence Tomography Angiography in the Operating Room in Young Children With Retinal Vascular Disease.

    Science.gov (United States)

    Chen, Xi; Viehland, Christian; Carrasco-Zevallos, Oscar M; Keller, Brenton; Vajzovic, Lejla; Izatt, Joseph A; Toth, Cynthia A

    2017-05-01

    Intraoperative optical coherence tomography (OCT) has gained traction as an important adjunct for clinical decision making during vitreoretinal surgery, and OCT angiography (OCTA) has provided novel insights in clinical evaluation of retinal diseases. To date, these two technologies have not been applied in combination to evaluate retinal vascular disease in the operating suite. To conduct microscope-integrated, swept-source OCTA (MIOCTA) in children with retinal vascular disease. In this case report analysis, OCT imaging in pediatric patients, MIOCTA images were obtained during examination under anesthesia from a young boy with a history of idiopathic vitreous hemorrhage and a female infant with familial exudative vitreoretinopathy. Side-by-side comparison of research MIOCT angiograms and clinically indicated fluorescein angiograms. In 2 young children with retinal vascular disease, the MIOCTA images showed more detailed vascular patterns than were visible on the fluorescein angiograms although within a more posterior field of view. The MIOCTA system allowed visualization of small pathological retinal vessels in the retinal periphery that were obscured in the fluorescein angiograms by fluorescein staining from underlying, preexisting laser scars. This is the first report to date of the use of MIOCTA in the operating room for young children with retinal vascular disease. Further optimization of this system may allow noninvasive detailed evaluation of retinal vasculature during surgical procedures and in patients who could not cooperate with in-office examinations.

  11. Grading of Age-Related Macular Degeneration: Comparison between Color Fundus Photography, Fluorescein Angiography, and Spectral Domain Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Nils F. Mokwa

    2013-01-01

    Full Text Available Purpose. To compare color fundus photography (FP, fluorescein angiography (FA, and spectral domain optical coherence tomography (SDOCT for the detection of age-related macular degeneration (AMD, choroidal neovascularisation (CNV, and CNV activity. Methods. FPs, FAs, and SDOCT volume scans from 120 eyes of 66 AMD and control patients were randomly collected. Control eyes were required to show no AMD, but other retinal pathology was allowed. The presence of drusen, pigmentary changes, CNV, and signs for CNV activity was independently analyzed for all imaging modalities. Results. AMD was diagnosed based on FP in 75 eyes. SDOCT and FA showed sensitivity (specificity of 89% (76% and 92% (82%, respectively. CNV was present on FA in 68 eyes. Sensitivity (specificity was 78% (100% for FP and 94% (98% for SDOCT. CNV activity was detected by SDOCT or FA in 60 eyes with an agreement in 46 eyes. Sensitivity was 88% for SDOCT and 88% for FA. FP showed sensitivity of 38% and specificity of 98%. Conclusions. CNV lesions and activity may be missed by FP alone, but FP may help identifying drusen and pigmentary changes. SDOCT is highly sensitive for the detection of AMD, CNV, and CNV activity; however, it cannot fully replace FA.

  12. Grading of Age-Related Macular Degeneration: Comparison between Color Fundus Photography, Fluorescein Angiography, and Spectral Domain Optical Coherence Tomography.

    Science.gov (United States)

    Mokwa, Nils F; Ristau, Tina; Keane, Pearse A; Kirchhof, Bernd; Sadda, Srinivas R; Liakopoulos, Sandra

    2013-01-01

    Purpose. To compare color fundus photography (FP), fluorescein angiography (FA), and spectral domain optical coherence tomography (SDOCT) for the detection of age-related macular degeneration (AMD), choroidal neovascularisation (CNV), and CNV activity. Methods. FPs, FAs, and SDOCT volume scans from 120 eyes of 66 AMD and control patients were randomly collected. Control eyes were required to show no AMD, but other retinal pathology was allowed. The presence of drusen, pigmentary changes, CNV, and signs for CNV activity was independently analyzed for all imaging modalities. Results. AMD was diagnosed based on FP in 75 eyes. SDOCT and FA showed sensitivity (specificity) of 89% (76%) and 92% (82%), respectively. CNV was present on FA in 68 eyes. Sensitivity (specificity) was 78% (100%) for FP and 94% (98%) for SDOCT. CNV activity was detected by SDOCT or FA in 60 eyes with an agreement in 46 eyes. Sensitivity was 88% for SDOCT and 88% for FA. FP showed sensitivity of 38% and specificity of 98%. Conclusions. CNV lesions and activity may be missed by FP alone, but FP may help identifying drusen and pigmentary changes. SDOCT is highly sensitive for the detection of AMD, CNV, and CNV activity; however, it cannot fully replace FA.

  13. Knowledge-based iterative model reconstruction in coronary computed tomography angiography: comparison with hybrid iterative reconstruction and filtered back projection.

    Science.gov (United States)

    Cha, Min Jae; Seo, Jae Seung; Yoo, Dong Soo; Chong, Semin

    2017-01-01

    Background Knowledge-based iterative model reconstruction (IMR) is known to allow radiation dose reduction while preserving image quality. Purpose To investigate the effect of IMR on coronary computed tomography angiography (CCTA) by comparing it with filtered back projection (FBP) and hybrid iterative reconstruction (HIR). Material and Methods Forty-five patients (group A) who underwent CCTA with prospective electrocardiogram (ECG) triggering at 80 kVp were included. All images were reconstructed using three algorithms: FBP, HIR, and IMR. The control group comprised 45 patients (group B) who underwent CCTA at 100 kVp; their images were reconstructed with HIR alone. Objective and subjective image quality was assessed by two radiologists. Results In group A, the signal-to-noise and contrast-to-noise ratios were significantly higher for images reconstructed with IMR than with HIR or FBP ( P HIR and FBP in subjective image quality analyses, including image noise, vessel sharpness, beam-hardening artifact, and overall quality ( P HIR in group B on both objective and subjective analyses ( P HIR and FBP, IMR provided higher quality images with less radiation exposure in CCTA, using low kilovoltage and prospective ECG triggering.

  14. Planning deep inferior epigastric perforator flaps for breast reconstruction: a comparison between multidetector computed tomography and magnetic resonance angiography

    Energy Technology Data Exchange (ETDEWEB)

    Cina, A.; Rinaldi, P.; Cipriani, A.; Bonomo, L. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Radiological Sciences, Rome (Italy); Barone-Adesi, L.; Salgarello, M. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Surgery, Plastic and Reconstructive Surgery Unit, Rome (Italy); Masetti, R. [Agostino Gemelli Hospital, Catholic University of Sacred Heart, Department of Surgery, Breast Surgery Unit, Rome (Italy)

    2013-08-15

    Deep inferior epigastric perforator (DIEP) flaps have become the state of the art in breast reconstruction. We compared the diagnostic performance of multidetector computed tomography (CTA) and magnetic resonance angiography (MRA) in DIEP flap planning. Twenty-three women (mean age 48.0 years, range 26-72 years) underwent preoperative blinded evaluation using 64-slice CTA and 1.5-T MRA. Perforator identification, measurement of their calibre, intramuscular course (IMC), assessment of direct venous connections (DVC) with main superficial veins, superficial venous communications (SVC) between the right and left hemi-abdomen and deep inferior epigastric artery (DIEA) branching type were performed. Surgery was carried out by the same team. Intraoperative findings were the standard of reference. Accuracy in identifying dominant perforators was 91.3 % for both techniques and mean error in calibre measurement 1.18 {+-} 0.35 mm for CTA and 1.63 {+-} 0.39 mm for MRA. Accuracy in assessing perforator IMCs was 97.1 % for CTA and 88.4 % for MRA, DVC 94.4 % for both techniques, SVC 91.3 % as well, and DIEA branching type 100 % for CTA and 91.3 % for MRA. Image acquisition and interpretation time was 21 {+-} 3 min for CTA (35 {+-} 5 min for MRA). In a strategy to optimise DIEP flap planning avoiding radiation exposure, MRA can be proposed alternatively to CTA. (orig.)

  15. Anatomical criteria of malignancy by computed tomography angiography in patients with anomalous coronary arteries with an interarterial course

    Energy Technology Data Exchange (ETDEWEB)

    Ashrafpoor, Golmehr [Assistance Publique-Hopitaux de Paris, Hopital Europeen Georges Pompidou, Universite Paris Descartes, Department of Radiology, Cardiovascular Imaging Unit, Paris (France); Danchin, Nicolas [Assistance Publique-Hopitaux de Paris, Hopital Europeen Georges Pompidou, Universite Paris Descartes, Department of Cardiology, Paris (France); Houyel, Lucile; Belli, Emre [Centre Chirurgical Marie-Lannelongue, Department of Congenital Cardiac Surgery, Le Plessis-Robinson (France); Ramadan, Ramzi [Centre Chirurgical Marie-Lannelongue, Department of Cardiac Surgery, Le Plessis-Robinson (France); Paul, Jean-Francois [Institut Mutualiste Montsouris, Department of Radiology, Paris (France)

    2014-10-11

    We sought to determine the relation between major adverse cardiac events (MACE) and anatomical criteria assessed by coronary computed tomography angiography (CCTA) in patients with an anomalous coronary artery with an interarterial course (ACAIAC). We selected CCTA studies of patients with an ACAIAC from a database of 4,160 examinations and studied anatomical criteria according to the presence of prior MACE, defined as syncope, unstable angina, myocardial infarction and resuscitated sudden cardiac death. There were 19 patients (18 males) with an ACAIAC during the study period (incidence 0.46 %). Seven patients with prior MACE were younger (26 years vs 59 years, p < 0.001), had a smaller minimal lumen area (3.6 mm{sup 2} vs 9.0 mm{sup 2}, p = 0.001), a higher degree of area stenosis (57 % vs 24 %, p = 0.001), a longer interarterial course (14.7 vs 8.6 mm, p = 0.003) and a smaller proximal segment width (1.6 mm vs 2.5 mm, p = 0.02) compared with the 12 patients without prior MACE. All patients with MACE had the following concomitant anatomical characteristics: minimum lumen area ≤4 mm{sup 2}, an area stenosis ≥50 % and intra-arterial length >10 mm Prior MACE is associated with specific anatomical CCTA characteristics among patients with ACAIAC. CCTA may therefore contribute to distinguish patients at risk of adverse events. (orig.)

  16. Prospectively gated coronary computed tomography angiography: uncompromised quality with markedly reduced radiation exposure in acute chest pain evaluation.

    Science.gov (United States)

    Goitein, Orly; Beigel, Roy; Matetzky, Shlomi; Kuperstein, Rafael; Brosh, Sella; Eshet, Yael; Di Segni, Elio; Konen, Eli

    2011-08-01

    Coronary computed tomography angiography (CCTA) is an established modality for ruling out coronary artery disease. However, it has been suggested that CCTA may be a source of non-negligible radiation exposure. To evaluate the potential degradation in coronary image quality when using prospective gated (PG) CCTA as compared with retrospective gated (RG) CCTA in chest pain evaluation. The study cohort comprised 216 patients: 108 consecutive patients in the PG CCTA arm and 108 patients matched for age, gender and heart rate in the RG CCTA arm. Scans were performed using a 64-slice multidetector CT scanner. All 15 coronary segments were evaluated subjectively for image quality using a 5-point visual scale. Dose-length product was recorded for each patient and the effective radiation dose was calculated The PG CCTA technique demonstrated a significantly higher incidence of step artifacts in the middle and distal right coronary artery, the distal left anterior descending artery, the second diagonal, the distal left circumflex artery, and the second marginal branches. Nevertheless, the diagnostic performance of these scans was not adversely affected. The mean effective radiation doses were 3.8 +/- 0.9 mSv vs.17.2 +/- 3 mSv for PG CCTA and RG CCTA, respectively (P acute chest pain "fast track" evaluation targeted at relatively young subjects in a chest pain unit.

  17. Interocular Symmetry of Vascular Density and Association with Central Macular Thickness of Healthy Adults by Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Liu, Guodong; Keyal, Khusbu; Wang, Fang

    2017-11-24

    In order to analyze the interocular correlation of vascular density, foveal avascular zone (FAZ) size, central macular thickness (CMT), and to investigate the relationship between vascular density and CMT in normal eyes, retinal vascular density in superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) networks, FAZ size, and CMT were visualized by optical coherence tomography (OCT) angiography. A total of 174 eyes of 87 normal Chinese subjects were enrolled in the study. The results showed that FAZ and CMT measurements are not statistically significant between right and left eyes, but right eyes had higher vascular density in superficial, deep retinal capillary and choriocapillaris networks, which might be related with dominant eyes. Spearman correlation test revealed a high correlation between right and left eyes for FAZ and CMT measurements (r = 0.934; r = 0.935), and a moderate correlation for SCP, DCP and CC density (r = 0.402; r = 0.666; r = 0.417). The analysis showed greater vascular density with smaller FAZ size, and a high negative relationship between FAZ and CMT, which indicates a positive correlation between retinal blood supply and retinal thickness.

  18. Computed tomography angiography intraluminal filling defect is predictive of internal carotid artery free-floating thrombus

    Energy Technology Data Exchange (ETDEWEB)

    Jaberi, A.; Lum, C.; Stefanski, P.; Iancu, D. [University of Ottawa, Faculty of Medicine, Ottawa, Ontario (Canada); The Ottawa Hospital, Department of Radiology, Neuroradiology Section, Ottawa, Ontario (Canada); Thornhill, R. [Neurosciences and Clinical Epidemiology Program/Methods Centre, Ottawa Hospital Research Institute, Ottawa, Ontario (Canada); The Ottawa Hospital, Department of Radiology, Neuroradiology Section, Ottawa, Ontario (Canada); Petrcich, W. [Neurosciences and Clinical Epidemiology Program/Methods Centre, Ottawa Hospital Research Institute, Ottawa, Ontario (Canada); Momoli, F. [Children' s Hospital of Eastern Ontario Research Institute, Ottawa, Ontario (Canada); University of Ottawa, Department of Epidemiology and Community Medicine, Ottawa, Ontario (Canada); Torres, C.; Dowlatshahi, D. [University of Ottawa, Faculty of Medicine, Ottawa, Ontario (Canada); University of Ottawa, Division of Neurology, Department of Medicine, Ottawa, Ontario (Canada)

    2014-01-15

    Filling defects at the internal carotid artery (ICA) origin in the work-up of stroke or transient ischemic attack may be an ulcerated plaque or free-floating thrombus (FFT). This may be challenging to distinguish, as they can appear morphologically similar. This is an important distinction as FFT can potentially embolize distally, and its management differs. We describe a series of patients with suspected FFT and evaluate its imaging appearance, clinical features, and evolution with therapy. Between 2008 and 2013, we prospectively collected consecutive patients with proximal ICA filling defects in the axial plane surrounded by contrast on CT/MR angiography. We defined FFT as a filling defect that resolved on follow-up imaging. We assessed the cranial-caudal dimension of the filling defect and receiver operating characteristics to identify clinical and radiological variables that distinguished FFT from complex ulcerated plaque. Intraluminal filling defects were identified in 32 patients. Filling defects and resolved or decreased in 25 patients (78 %) and felt to be FFT; there was no change in 7 (22 %). Resolved defects and those that decreased in size extended more cranially than those that remained unchanged: 7.3 mm (4.2-15.9) versus 3.1 mm (2.7-3.7; p = 0.0038). Receiver operating characteristic analysis established a threshold of 3.8 mm (filling defect length), sensitivity of 88 %, specificity of 86 %, and area under the curve of 0.86 (p < 0.0001) for distinguishing FFT from plaque. Filling defects in the proximal ICA extending cranially >3.8 mm were more likely to be FFT than complex ulcerated plaque. Further studies evaluating filling defect length as a predictor for FFT are warranted. (orig.)

  19. Computed Tomography Angiography With High Flow Rates: An In Vitro and In Vivo Feasibility Study.

    Science.gov (United States)

    Mihl, Casper; Kok, Madeleine; Wildberger, Joachim E; Turek, Jakub; Muehlenbruch, Georg; Das, Marco

    2015-07-01

    The aims of this study were to test high-flow application of contrast media (CM) using novel high-flow needles and to assess injection- and flow-related parameters in a circulation phantom and in an in vivo population. A circulation phantom simulating physiological parameters was used. Preheated CM (300 mg/mL) was injected at flow rates varying between 5 and 15 mL/s through a novel 18-gauge high-flow intravenous injection needle. In addition, feasibility of these high-flow needles was tested with administration of flow rates of 9 mL/s in 20 patients referred for pre-transcatheter aortic valve implantation assessment. Injection parameters (eg, peak pressures, peak flow rates) in both phantom and in vivo setup were continuously monitored by a data acquisition program. Attenuation at predefined levels of the aorta (eg, aortic root to common femoral arteries) was measured in all patients to determine clinical applicability. In the phantom setup, injection rates up to 15 mL/s were feasible. An enhancement plateau was reached at 11 mL/s (464 [20] HU). In patients, no pressure- or flow-related complications (eg, extravasation) were recorded (mean [SD] peak pressure, 154 [8] psi; mean [SD] peak flow rate, 9.2 [0.1 mL/s; range, 9.1-9.6]). Diagnostic attenuation values were reached at all predefined levels of the aorta (330.8 [113.1] HU to 622.9 [81.5] HU). These results indicate that injections with 9 mL/s using high-flow injection needles are safe. The pressure limit of 325 psi was not reached, and the injections resulted in diagnostic attenuation values. Using this dedicated needle, high flow rates should not be considered a drawback for CM application in routine CT angiography examinations.

  20. Contrast media administration in coronary computed tomography angiography. A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Mihl, Casper; Kok, Madeleine; Wildberger, Joachim E.; Das, Marco [Maastricht Univ. Medical Center (Netherlands). CARIM School for Cardiovascular Diseases; Maastricht Univ. Medical Center (Netherlands). Radiology; Maas, Monique; Lobbes, Marc B.I. [Maastricht Univ. Medical Center (Netherlands). Radiology; Turek, Jakub; Seehofnerova, Anna [Maastricht Univ. Medical Center (Netherlands). CARIM School for Cardiovascular Diseases; Leijenaar, Ralph T.H. [GROW School for Oncology and Developmental Biology, Maastricht (Netherlands). Radiation Oncology (MAASTRO)

    2017-04-15

    Various different injection parameters influence enhancement of the coronary arteries. There is no consensus in the literature regarding the optimal contrast media (CM) injection protocol. The aim of this study is to provide an update on the effect of different CM injection parameters on the coronary attenuation in coronary computed tomographic angiography (CCTA). Studies published between January 2001 and May 2014 identified by Pubmed, Embase and MEDLINE were evaluated. Using predefined inclusion criteria and a data extraction form, the content of each eligible study was assessed. Initially, 2551 potential studies were identified. After applying our criteria, 36 studies were found to be eligible. Studies were systematically assessed for quality based on the validated Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-II checklist. Extracted data proved to be heterogeneous and often incomplete. The injection protocol and outcome of the included publications were very diverse and results are difficult to compare. Based on the extracted data, it remains unclear which of the injection parameters is the most important determinant for adequate attenuation. It is likely that one parameter which combines multiple parameters (e.g. IDR) will be the most suitable determinant of coronary attenuation in CCTA protocols. Research should be directed towards determining the influence of different injection parameters and defining individualized optimal IDRs tailored to patient-related factors (ideally in large randomized trials). Key points: This systematic review provides insight into decisive factors on coronary attenuation. Different and contradicting outcomes are reported on coronary attenuation in CCTA. One parameter combining multiple parameters (IDR) is likely decisive in coronary attenuation. Research should aim at defining individualized optimal IDRs tailored to individual factors. Future directions should be tailored towards the influence of different injection

  1. Computerized tomography technique for reconstruction of obstructed phase data in shearography.

    Science.gov (United States)

    Hung, Y Y; Huang, Y H; Liu, L; Ng, S P; Chen, Y S

    2008-06-10

    Shearography is an interferometric method that overcomes several limitations of holography by eliminating the reference beam. It greatly simplifies the optical setup and has much higher tolerance to environmental disturbances. Consequently, the technique has received considerable industrial acceptance, particularly for nondestructive testing. Shearography, however, is generally not applicable to the measurement of an obstructed area, as the area to be measured must be accessible to both illumination and imaging. We present an algorithm based on the principle of tomography that permits the reconstruction of the unavailable phase distribution in an obstructed area from the measured boundary phase distribution. In the process, a set of imaginary rays is projected from many different directions across the area. For each ray, integration of the phase directional derivative along the ray is equal to the phase difference between the boundary points intercepted by the ray. Therefore, a set of linear equations can be established by considering the multiple rays. Each equation expresses the unknown phase derivatives in the obstructed area in terms of the measured boundary phase. Solution of the set of simultaneous equations yields the unknown phase distribution in the blind area. While its applications to shearography are demonstrated, the technique is potentially applicable to all full-field optical measurement techniques such as holography, speckle interferometry, classical interferometry, thermography, moiré, photoelasticity, and speckle correlation techniques.

  2. Signs and symptoms after temporomandibular joint washing and cannula placement assessed by cone beam computerized tomography.

    Science.gov (United States)

    Kristensen, Kasper Dahl; Stoustrup, Peter; Alstergren, Per; Küseler, Annelise; Herlin, Troels; Pedersen, Thomas Klit

    2015-08-01

    Analyses of temporomandibular joint synovial fluid using the hydroxocobalamin push-pull technique are increasingly used. However, objective complications and subjective experiences from this procedure have not been described. Firstly, this study aimed to describe discomfort and potential side-effects of this method with special emphasis on symptoms related to the arthrocentesis to be used for future patient information and Ethical Committee applications. Secondly, this study aimed to evaluate the use of cone beam computed tomography (CBCT) as control of intra-capsular cannula placement. Twenty healthy, young adult volunteers were included. Extensive objective and subjective questionnaires were completed before and 14 days after the synovial fluid sampling. With the cannula inside the joints a CBCT was done to investigate if this procedure can be used to verify intra-capsular cannula position. The subjective findings: Most subjects did experience mild pain or discomfort post-operatively. In 12 of 20 subjects symptoms had resolved after 2 days and no subjects had symptoms for more than a week. The longer lasting symptoms were mainly transient joint sounds on mandibular movement. Objective findings: 14 days after the sampling mandibular protrusion had improved 1 mm, but all other objective measures were equal compared to baseline. CBCT showed a large variation in cannula position and no conclusions could be drawn from this. The hydroxocobalamin push-pull synovial fluid sampling may cause minor, transient symptoms. CBCT does not seem to provide any clinical benefits concerning the correct cannula position in relation to the upper joint compartment and disc.

  3. Maxillofacial injuries among trauma patients undergoing head computerized tomography; A Ugandan experience.

    Science.gov (United States)

    Krishnan, Ullas Chandrika; Byanyima, Rosemary Kusaba; Faith, Ameda; Kamulegeya, Adriane

    2017-01-01

    The aim of this study was to investigate epidemiological features of maxillofacial fractures within trauma patients who had head and neck computed tomography (CT) scan at the Mulago National referral hospital. CT scan records of trauma patients who had head scans at the Department of Radiology over 1-year period were accessed. Data collected included sociodemographic factors, type and etiology of injury, and concomitant maxillofacial injuries. A total of 1330 trauma patients underwent head and neck CT scan in the 1-year study period. Out of these, 130 were excluded due to incomplete or unclear records and no evidence of injury. Of the remaining 1200, 32% (387) had maxillofacial fractures. The median age of the patients with maxillofacial fractures was 28 (range = 18-80) years and 18-27 age group was most common at 47.5%. Road traffic accidents constituted 49.1% of fractures. The single most affected isolated bone was the frontal bone (23%). The number of maxillofacial bones fractured was predicted by age group (df = 3 F = 5.358, P = 0.001), association with other fractures (df = 1 F = 5.317, P = 0.03). Good matched case-control prospective studies are needed to enable us tease out the finer difference in the circumstances and pattern of injury if we are to design appropriate preventive measures.

  4. Computerized Tomography-Guided Stereotactic Biopsy of Intracranial Lesions: Report of 500 Consecutive Cases.

    Science.gov (United States)

    Can, Songul Meltem; Turkmenoglu, Osman Nuri; Tanik, Canan; Uysal, Ender; Ozoner, Baris; Kaldirimoglu, Saime Ayca; Musluman, Ahmet Murat; Yilmaz, Adem; Cavusoglu, Halit; Bayindir, Cicek; Aydin, Yunus

    2017-01-01

    Computed tomography (CT)-guided stereotactic brain biopsy has been performed in our clinic since March 1998. In this prospective study, we examined the patient data undergoing stereotactic biopsy and the results of biopsies in 500 consecutive patients. Between the dates of March 1998 and January 2015, CT-guided stereotactic biopsies were performed by using the Leksell stereotactic frame system (Elekta Instruments EU, Sweden) in 500 patients. A total of 512 procedures were performed in patients consisting of 184 females (36.8%) and 316 males (63.2%), ages ranging from 3 to 81 years (mean 50.40±16.67). Conclusive histopathological diagnosis was not achieved in 17(3.3%) of 512 procedures. Of the others, 173 (33.8%) were high-grade gliomas, 103 (20.1%) were low-grade gliomas, 36 (7%) were malignant lymphomas, 34 (6.6%) were other types of brain tumors, 82 (16%) were metastasis and 67 (13.1%) were non-tumoral lesions. Complications were occurred in ten cases: 3 tumoral bleedings, 2 hypertensive cerebral hematomas, 2 peroperative convulsions, 1 epidural hematoma, 1 myocardial infarction and 1 brain edema. The patients who developed myocardial infarction and hypertensive thalamic hematoma died. The mortality was 0.4% and morbidity was 1.6% in 512 procedures. CT-guided stereotactic biopsy is a reliable and a safe procedure in cases with intracranial lesions when histopathological diagnosis is required for the appropriate treatment.

  5. Direct costs and cost-effectiveness of dual-source computed tomography and invasive coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease.

    Science.gov (United States)

    Dorenkamp, Marc; Bonaventura, Klaus; Sohns, Christian; Becker, Christoph R; Leber, Alexander W

    2012-03-01

    The study aims to determine the direct costs and comparative cost-effectiveness of latest-generation dual-source computed tomography (DSCT) and invasive coronary angiography for diagnosing coronary artery disease (CAD) in patients suspected of having this disease. The study was based on a previously elaborated cohort with an intermediate pretest likelihood for CAD and on complementary clinical data. Cost calculations were based on a detailed analysis of direct costs, and generally accepted accounting principles were applied. Based on Bayes' theorem, a mathematical model was used to compare the cost-effectiveness of both diagnostic approaches. Total costs included direct costs, induced costs and costs of complications. Effectiveness was defined as the ability of a diagnostic test to accurately identify a patient with CAD. Direct costs amounted to €98.60 for DSCT and to €317.75 for invasive coronary angiography. Analysis of model calculations indicated that cost-effectiveness grew hyperbolically with increasing prevalence of CAD. Given the prevalence of CAD in the study cohort (24%), DSCT was found to be more cost-effective than invasive coronary angiography (€970 vs €1354 for one patient correctly diagnosed as having CAD). At a disease prevalence of 49%, DSCT and invasive angiography were equally effective with costs of €633. Above a threshold value of disease prevalence of 55%, proceeding directly to invasive coronary angiography was more cost-effective than DSCT. With proper patient selection and consideration of disease prevalence, DSCT coronary angiography is cost-effective for diagnosing CAD in patients with an intermediate pretest likelihood for it. However, the range of eligible patients may be smaller than previously reported.

  6. CT coronary angiography vs. invasive coronary angiography in CHD

    OpenAIRE

    Anja Hagen; Schönermark, Matthias P.; Vitali Gorenoi

    2012-01-01

    Scientific background Various diagnostic tests including conventional invasive coronary angiography and non-invasive computed tomography (CT) coronary angiography are used in the diagnosis of coronary heart disease (CHD). Research questions The present report aims to evaluate the clinical efficacy, diagnostic accuracy, prognostic value cost-effectiveness as well as the ethical, social and legal implications of CT coronary angiography versus invasive coronary angiography in the diagnosis of C...

  7. Peripapillary retinal vessel density in eyes with acute primary angle closure: an optical coherence tomography angiography study.

    Science.gov (United States)

    Wang, Xiaolei; Jiang, Chunhui; Kong, Xiangmei; Yu, Xiaobo; Sun, Xinghuai

    2017-05-01

    The purpose was to investigate peripapillary retinal vessel density in resolved acute primary angle closure (APAC) eyes. This was a prospective, cross-sectional observational study. Thirty-four eyes of 34 patients with unilateral APAC were included, together with the fellow eyes with primary angle closure suspect (PACS) as controls. Peripapillary retinal vessel density was measured using optical coherence tomography (OCT) angiography. Peripapillary retinal vessel density was compared in both eyes and the potential relationship with visual field (VF) test results was evaluated. After an acute attack, the peripapillary retinal vessel density was lower in the APAC than in the PACS eyes (79.3 ± 8.2 versus 85.6 ± 4.9, respectively; P = 0.001). The VF mean deviation (MD) (-7.7 ± 6.7 versus -3.3 ± 1.8 dB, P = 0.002), and the pattern standard deviation (PSD) (4.6 ± 3.3 versus 2.4 ± 0.9 dB, P = 0.001) were worse for the APAC than the PACS eyes, but both had similar thicknesses of the retinal nerve fiber layer (RNFL) (111.8 ± 9.6 versus 114.1 ± 29.1 μm, P = 0.880) and ganglion cell complex (GCC) (94.7 ± 7.5 versus 91.8 ± 9.3 μm, P = 0.328). The peripapillary retinal vessel density was significantly correlated with the VF MD (vessel density: r = 0.455, P = 0.008) and PSD (vessel density: r = -0.592, P density, which was correlated with the VF values. OCT angiography is a reliable method for detecting vascular changes in glaucomatous eyes that show no thinning of the RNFL and GCC.

  8. Image Quality in Oncologic Chest Computerized Tomography With Iterative Reconstruction: A Phantom Study.

    Science.gov (United States)

    Jensen, Kristin; Aaløkken, Trond Mogens; Tingberg, Anders; Fosse, Erik; Martinsen, Anne Catrine T

    2016-01-01

    The purpose of this study was to validate iterative reconstruction technique in oncologic chest computed tomography (CT). An anthropomorphic thorax phantom with 4 simulated tumors was scanned on a 64-slice CT scanner with 2 different iterative reconstruction techniques: one model based (MBIR) and one hybrid (ASiR). Dose levels of 14.9, 11.1, 6.7, and 0.6 mGy were used, and all images were reconstructed with filtered back projection (FBP) and both iterative reconstruction algorithms. Hounsfield units (HU) and absolute noise were measured in the tumors, lung, heart, diaphragm, and muscle. Contrast-to-noise ratios (CNRs) and signal-to-noise ratios (SNRs) were calculated. Model-based iterative reconstruction (MBIR) increased CNRs of the tumors (21.1-192.2) and SNRs in the lung (-49.0-165.6) and heart (3.1-8.5) at all dose levels compared with FBP (CNR, 1.1-23.0; SNR, -7.5-31.6 and 0.2-1.1) and with adaptive statistical iterative reconstruction (CNR, 1.2-33.2; SNR, -7.3-37.7 and 0.2-1.5). At the lowest dose level (0.6 mGy), MBIR reduced the cupping artifact (HU range: 17.0 HU compared with 31.4-32.2). An HU shift in the negative direction was seen with MBIR. Quantitative image quality parameters in oncologic chest CT are improved with MBIR compared with FBP and simpler iterative reconstruction algorithms. Artifacts at low doses are reduced. A shift in HU values was shown; thus, absolute HU values should be used with care.

  9. Utility of mobile devices in the computerized tomography evaluation of intracranial hemorrhage

    Directory of Open Access Journals (Sweden)

    Sridhar G Panughpath

    2013-01-01

    Full Text Available Aim: To evaluate the utility of a mobile device to detect and assess intracranial hemorrhage (ICH on head computed tomographys (CT performed in the emergency setting. Materials and Methods: 100 head CT scans were randomly selected from our emergency radiology database and anonymized for patient demographics and clinical history. The studies were independently interpreted by two experienced radiologists in a blinded manner, initially on a mobile device (iPad, Apple computers and subsequently, at an interval of one week, on a regular desktop workstation. Evaluation was directed towards detection, localization and characterization of hemorrhage. The results were assessed for accuracy, sensitivity, specificity and positive predictive value. Statistical significance was ascertained using Fisher′s exact test. Results: 27 of the examinations were positive for ICH, of which 11 had multiple hemorrhages. Of these there were 17 subdural, 18 intraparenchymal, 8 subarachnoid, 4 intraventricular and 2 extradural hemorrhages. In 96 of the studies there was complete concurrence between the iPad and desktop interpretations for both radiologists. Of 49 hemorrhages, 48 were accurately detected on the iPad by one of the radiologists. In the remaining case, a tiny intraventricular hemorrhage was missed by both radiologists on the iPad as well as on the workstation, indicating that the miss was more likely related to the very small size of the hemorrhage than the viewer used. Conclusion: We conclude that in the emergency setting, a mobile device with appropriate web-based pictue archiving and communication system (PACS is effective in the detection of intracranial hemorrhage present on head CT.

  10. Dose assessment in pediatric computerized tomography; Avaliacao de doses em tomografia computadorizada pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Vilarinho, Luisa Maria Auredine Lima

    2004-07-01

    The objective of this work was the evaluation of radiation doses in paediatric computed tomography scans, considering the high doses usually involved and the absence of any previous evaluation in Brazil. Dose values were determined for skull and abdomen examinations, for different age ranges, by using the radiographic techniques routinely used in the clinical centers investigated. Measurements were done using pencil shape ionization chambers inserted in polymethylmethacrylate (PMMA) phantoms. These were compact phantoms of different diameters were specially designed and constructed for this work, which simulate different age ranges. Comparison of results with published values showed that doses were lower than the diagnostic reference levels established to adults exams by the European Commission. Nevertheless, doses in paediatric phantoms were higher than those obtained in adult phantoms. The paediatric dose values obtained in Hospitals A and B were lower than the reference level (DRL) adopted by SHIMPTON for different age ranges. In the range 0 - 0.5 year (neonatal), the values of DLP in Hospital B were 94 por cent superior to the DRL For the 10 years old children the values of CTDI{sub w} obtained were inferior in 89 por cent for skull and 83 por cent for abdomen examinations, compared to the values published by SHRIMPTON and WALL. Our measured CTDI{sub w} values were inferior to the values presented for SHRIMPTON and HUDA, for all the age ranges and types of examinations. It was observed that the normalized dose descriptors values in children in the neonatal range were always superior to the values of doses for the adult patient. In abdomen examinations, the difference was approximately 90% for the effective dose (E) and of 57%.for CTDI{sub w} . (author)

  11. Computed tomography angiography: the effect of different chaser flow rates, volumes, and fluids on contrast enhancement.

    Science.gov (United States)

    Behrendt, Florian F; Jost, Gregor; Pietsch, Hubertus; Keil, Sebastian; Mottaghy, Felix M; Günther, Rolf W; Mahnken, Andreas H

    2011-04-01

    The aim of this study was to intraindividually compare the effect of different chaser flow rates, volumes, and fluids on contrast enhancement in multidetector-row computed tomography. Multidetector-row computed tomography scanning of 5 dogs was performed under standardized conditions using an adapted injection protocol to ensure an identical iodine delivery rate of 1.0 gI/s and a total iodine dose of 300 mg/kg body weight (iopromide 300 and 370). The contrast medium application was followed by a 10-mL saline chaser at different injection rates (0, 2.7, 4, 6, and 8 mL/s) or by different saline chaser volumes (0, 5, 10, and 15 mL) at a flow rate of 4 mL/s. Furthermore, different chaser fluids (NaCl, hydroxyethyl starch 10%, and Dextran 1%) with different viscosities (hydroxyethyl starch 10% and dextran 1%: 3.28 and 5.98 mPa · s at 37°C) were tested (volume: 10 mL; flow rate: 6 mL/s). Each dog was examined with each protocol. The interval between each computed tomography scan session which included 2 measurements was at least 3 days. Dynamic computed tomography scans were acquired at the level of the cephalic vein, cranial vena cava, pulmonary artery, and ascending and descending aorta. Time-enhancement curves were computed, and pulmonary and aortic peak enhancements as well as time-to-peak were analyzed. Increased saline chaser flow rates or increased saline chaser volumes resulted in increased pulmonary and aortic peak contrast enhancement. Peak enhancement was highest and significantly greater compared with no saline chaser for a flow rate of 8 mL/s (pulmonary artery: 816.8 vs. 471.5 HU, P = 0.0079; ascending aorta: 578.7 vs. 384.1 HU, P = 0.0079; descending aorta: 581.4 HU vs. 390.6 HU, P = 0.0159) and a saline volume of 15 mL (pulmonary artery: 670.2 vs. 453.5 HU, P = 0.0079; ascending aorta: 512.1 vs. 370.6 HU, P = 0.0317; descending aorta: 504.0 HU vs. 394.4 HU, P = 0.0159). No significant differences between the peak times for different saline chasers were

  12. Catheter Angiography

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    Full Text Available ... What are the limitations of Catheter Angiography? What is Catheter Angiography? Angiography is a minimally invasive medical ... top of page What are some common uses of the procedure? Catheter angiography is used to examine ...

  13. [Gunshot wounds of the cranium studied with computerized tomography. Personal experience in 23 cases].

    Science.gov (United States)

    Salzano, A; De Rosa, A; Scialpi, M; Rossi, E; Carbone, M; Brunese, L; Nocera, V; Muto, M

    2000-01-01

    Gunshot wounds to the head are usually mortal injuries. Their frequency has been increasing in the last years because of increasing crime rates. Gunshot wounds to the head require close clinical and diagnostic cooperation of the neurosurgeon and radiologist, detailed assessment of skull and brain damage, and finally prompt treatment. Emergency Computed Tomography (CT) makes a useful tool for depicting bullet course and brain damage, and thus helps plan treatment. We investigated the CT signs of subdural hematoma, lacerocontusive focus, subarachnoid hemorrhage, hemoencephalus, skull bone fracture and thecal hollow and report them as an aid to the neurosurgeon and the radiologist, for best treatment planning, and in an attempt to establish useful prognostic criteria. We retrospectively reviewed 23 cases of gunshot injuries to the head studied with CT at the Emergency Unit of Loreto Mare Hospital in Naples, Italy. Twenty patients were men and 3 women; their mean age was 31 years (range: 18-49). Three women and 2 men had been injured accidentally by wandering bullets, and one case was an attempted suicide; all the other cases resulted from shootings. CT slices were 10 mm thick, with 8 mm gap (5 mm in complex injuries and when posterior cranial fossa was involved); all scans were unenhanced. We found 22 penetrating gunshot wounds: 13 of them with thecal entry hole and intracranial bullet retention and 9 with an entry and an exit hole. One case was a superficial wound. Crash skull fractures were seen in 22 cases and they were fragmented in 12, with overlapping thecal fragments in 4, and with deep fragments in 2 cases. There were scattered bone splinters in 3 cases and the bullet was retained in the mastoid bone in one case. Lacerocontusive foci were assessed in 22 cases, brain swelling in 20, subarachnoid hemorrhage in 19, brain hematoma in 15, blood in the ventricular system in 9, pneumoencephalus in 7, air bubbles along the bullet course in 7, impression on ventricula

  14. A comparative analysis of periapical radiography and cone-beam computerized tomography for the evaluation of endodontic obturation length.

    Science.gov (United States)

    Cheng, Li; Zhang, Ru; Yu, Xuan; Tian, Yuanyuan; Wang, Hu; Zheng, Guangning; Hu, Tao

    2011-09-01

    The aim of this study was to determine the consistency and inconsistency between the periapical radiography (PR) and cone-beam computerized tomography (CBCT) in evaluating the length of root canal obturations (RCOs) in vivo. Thirty-six maxillary and mandibular first and second molars yielding 109 obturated root canals with available PR and CBCT images were analyzed. The inclusion criterion was that the RCO extended 0-2 mm short of the radiographic apex on PR images. Teeth having root canal calcification, apical resorption, or poor quality PR/CBCT images were excluded. Agreement and disagreement between the 2 imaging modalities for obturation length were analyzed using the χ(2) test. A total of 30.3% of the RCOs evaluated by PR as having adequate length were diagnosed by CBCT to have inadequate length. Among these, 13.8% were overextended and 16.5% underextended as diagnosed by CBCT. When the distance from the filling tip to the radiographic apex was 0.5 to 1 mm on the PR image, the discordance rate was the lowest (11.1%) in all evaluated distance groups, significantly lower than with distances of 0-0.5 mm and 1.5-2 mm (P lingual side, overextension was the main evaluation result by CBCT in the disagreement evaluation with PR and significantly more frequent than those at the mesial/distal/central side (P < .01). CBCT evaluated 30.3% of the RCOs with radiographically adequate length as inadequate. When the RCOs radiographically terminated 0.5-1 mm short of the apex, the evaluation rated adequate for obturation length was comparatively reliable. Copyright © 2011 Mosby, Inc. All rights reserved.

  15. Micro-computerized tomography assessment of fluorescence aided caries excavation (FACE) technology: comparison with three other caries removal techniques.

    Science.gov (United States)

    Zhang, X; Tu, R; Yin, W; Zhou, X; Li, X; Hu, D

    2013-12-01

    The aim of this study was to determine the caries removal effectiveness (CRE) and minimal invasiveness potential (MIP) of four dentine caries removal methods. After carious molars were scanned using micro-computerized tomography (micro-CT), dentine caries were removed by fluorescence aided caries excavation (FACE) technology, laser induced fluorescence (LIF), chemomechanical excavation (CME), and conventional excavation (CE). Micro-CT was then repeated. CRE was determined based on the volume of residual caries/initial caries (RC/IC) and the mean mineral density (MD) at the cavity floor. MIP was determined by measuring the volume of the prepared cavity/initial cavity (PC/IC). Among the four groups, the LIF group had the smallest RC/IC (0.08), the highest mean MD at the cavity floor (1.32 g/cm(3) ) and the highest MIP (4.47). The CME group had the highest RC/IC (0.24), the lowest mean MD (1.01 g/cm(3) ) and the lowest MIP (2.23). The CE group exhibited a more acceptable CRE (RC/IC = 0.13, mean MD = 1.21 g/cm(3) ) but had a higher MIP (3.95). Both the CRE and MIP parameters of FACE technology were the second most acceptable (RC/IC = 0.12, mean MD = 1.13 g/cm(3) , MIP = 3.20) and did not differ significantly from the most acceptable. FACE is an effective caries removal technology for removing infected dentine without significantly increasing cavity size. © 2013 Australian Dental Association.

  16. Computerized tomography in evaluation of decreased acetabular and femoral anteversion; Besonderheiten bei der Bestimmung der Hueftpfannenanteversion und Schenkelhalsantetorsion durch Computertomographie

    Energy Technology Data Exchange (ETDEWEB)

    Toennis, D.; Skamel, H.J. [Institut fuer Strahlendiagnostik, Klinikum Dortmund GmbH (Germany)

    2003-09-01

    Computerized tomography has received a new importance. It has been shown that decreased anteversion of femur and acetabulum, when both have decreased angles, are causing pain and osteoarthritis of the hip joint. Operative treatment should be performed before osteoarthritis develops. Exact measurements therefore are necessary. The investigation should be performed in prone position to have the pelvis lying in a defined and normal position. Femoral torsion is measured between the transverse axis of the knee and the femoral neck. The transverse axis for measurement of the femoral anteversion is defined by a rectangular line to the sagittal plane. For evaluation of the femoral anteversion in total the angle of the condyles has to be added to the femoral neck angle when the knee is found in internal rotation. Acetabular anteversion should be measured at the level where the femoral head is still in full contact and congruence with the anterior margin of the acetabulum. (orig.) [German] Fuer die Computertomographie hat sich eine neue Aufgabe ergeben. Es hat sich gezeigt, dass verringerte Pfannenanteversion und Schenkelhalsantetorsion haeufige Ursachen von Hueftschmerz und -arthrose sind, v. a. wenn beide gegen 0 gehen. Da operative Massnahmen vor Eintreten der Arthrose ergriffen werden sollten, sind genaue Messwerte erforderlich. Die Untersuchung sollte in Bauchlage durchgefuehrt werden, um eine einheitliche und weitgehend normale Beckenkippung zu gewaehrleisten. Die Schenkelhalstorsion wird zwischen der Kniegelenk- und der Schenkelhalsachse gemessen. Zur Festlegung der Sagittalebene legt man am besten eine Mittellinie zwischen die Beckenschaufeln. Die Messung der Pfannenanteversion sollte in der Schnitthoehe erfolgen, wo die Bewegungseinschraenkung der Innenrotation auftritt. (orig.)

  17. Meta-analysis of diagnostic significance of sixty-four-row multi-section computed tomography angiography and three-dimensional digital subtraction angiography in patients with cerebral artery aneurysm.

    Science.gov (United States)

    Guo, Wei; He, Xu-Ying; Li, Xi-Feng; Qian, Dong-Xiang; Yan, Jian-Quan; Bu, De-Lin; Duan, Chuan-Zhi

    2014-11-15

    Imaging methods are essential in evaluating cerebral artery aneurysms and they have evolved with recent technical advances. Sixty-four-row multi-section computed tomography (64-MSCT) angiography and three-dimensional digital subtraction angiography (3D-DSA) are two of the most popular methods. We sought to systematically explore and find out which one would be better in imaging cerebral artery aneurysm, and try to investigate the potential use and value of 64-MSCT angiography and 3D-DSA in cerebral artery aneurysm. Followed by a predefined comprehensive literature search, we carefully searched both English and Chinese electronic databases for potentially relevant studies following our meta-analysis. Two reviewers independently assessed the methodological quality of the included eligible trials based on quality assessment of studies of diagnostic accuracy studies (QUADAS). Pooled summary statistics for sensitivity, specificity, positive and negative likelihood ratios (positive LR and negative LR), and diagnostic odds ratio (ORs) with their 95% confidence intervals (CIs) were utilized. Final meta-analysis of 923 cerebral artery aneurysm cases were incorporated from eight cohort studies and selected for statistical analysis. Pooled sensitivity and specificity of 64-MSCT angiography in the diagnosis of cerebral artery aneurysm were 0.97 (95% CI, 0.96-0.98) and 0.91 (0.88-0.94), respectively. The pooled positive LR was 7.68 (95% CI, 3.34-17.67); and the pooled negative LR was 0.04 (95% CI, 0.03-0.05). The pooled diagnostic OR was 263.69 (95% CI, 121.19-573.77). The area under the SROC curve was 0.9934 (standard error [SE] = 0.0031). No significant evidence of publication bias was detected (P > 0.05). The main finding of our meta-analysis revealed that 64-MSCT angiography relative to the 3D-DSA may have a high diagnostic accuracy for the cerebral artery aneurysm. Thus, 64-MSCT angiography may be an effective tool for the early detection of cerebral artery aneurysm

  18. [Application of spiral computerized tomography in the study of traumatic lesions of the thoracic aorta].

    Science.gov (United States)

    Mengozzi, E; Burzi, M; Miceli, M; Lipparini, M; Sartoni Galloni, S

    2000-09-01

    Acute thoracic aortic injuries account for up to 10-20% of fatalities in high-speed deceleration road accidents and have an estimated immediate fatality rate of 80-90%. Untreated survivors to acute trauma (10-20%) have a dismal prognosis: 30% of them die within 6 hours, 40-50% die within 24 hours, and 90% within 4 months. We investigated the diagnostic accuracy of Helical Computed Tomography (Helical CT) in acute traumatic injuries of the thoracic aorta, and the role of this technique in the diagnostic management of trauma patients with a strong suspicion of aortic rupture. We compared retrospectively the chest Helical CT findings of 256 trauma patients examined June 1995 through August 1999. All patients underwent a plain chest radiograph in supine recumbency when admitted to the Emergency Room. Chest Helical CT examinations were performed according to trauma score, to associated traumatic lesions and to plain chest radiographic findings. All the examinations were performed with no intravenous contrast agent administration and the pitch 2 technique. After a previous baseline study, contrast-enhanced scans were acquired with pitch 1 in 87 patients. All examinations were assessed for the presence of mediastinal hematoma, periaortic hematoma, traumatic pseudodiverticulum, irregular aortic wall or contour and intimal flap as signs of aortic rupture. Helical CT showed thoracic aortic lesions in 9 of 256 patients examined. In all the 9 cases we found a mediastinal hematoma and all of them had positive plain chest radiographic findings of mediastinal enlargement. Moreover, in 6 cases aortic knob blurring was also evident on plain chest film and in 5 cases depressed left mainstem bronchus and trachea deviation rightwards were observed. All aortic lesions were identified on axial scans and located at the isthmus of level. Aortic rupture was always depicted as pseudodiverticulum of the proximal descending tract and intimal flap. We also found periaortic hematoma in 6 cases

  19. Macular laser photocoagulation guided by spectral-domain optical coherence tomography versus fluorescein angiography for diabetic macular edema

    Directory of Open Access Journals (Sweden)

    Gallego-Pinazo R

    2011-05-01

    Full Text Available Roberto Gallego-Pinazo1,2, Ana Marina Suelves-Cogollos1, Rosa Dolz-Marco1, J Fernando Arevalo3, Salvador García-Delpech1, J Luis Mullor4, Manuel Díaz-Llopis1,2,51Department of Ophthalmology, Hospital Universitario La Fe, Valencia, Spain; 2Centro de Investigación Biomédica en Red de Enfermedades Raras, Valencia, Spain; 3Retina and Vitreous Service, Clinical Ophthalmology Center, Caracas, Venezuela; 4Unit of Experimental Ophthalmology, Hospital Universitario La Fe, Valencia, Spain; 5University of Valencia, Faculty of Medicine, Valencia, SpainBackground: The aim of this study was to compare the efficacy of spectral-domain optical coherence tomography (SD-OCT and fluorescein angiography (FA in the guidance of macular laser photocoagulation for diabetic macular edema.Methods: This was a prospective interventional clinical comparative pilot study. Forty eyes from 24 consecutive patients with diabetic macular edema were allocated to receive laser photocoagulation guided by SD-OCT or FA. Best-corrected visual acuity (BCVA, central macular thickness, and retinal volume were assessed at baseline and two months after treatment.Results: Subjects treated using FA-guided laser improved BCVA from the logarithm of the minimum angle of resolution (logMAR 0.52 ± 0.2 to 0.37 ± 0.2 (P < 0.001, and decreased mean central macular thickness from 397.25 ± 139.1 to 333.50 ± 105.7 µm (P < 0.001 and retinal volume from 12.61 ± 1.6 to 10.94 ± 1.4 mm3 (P < 0.001. Subjects treated using SD-OCT guided laser had improved BCVA from 0.48 ± 0.2 to 0.33 ± 0.2 logMAR (P < 0.001, and decreased mean central macular thickness from 425.90 ± 149.6 to 353.4 ± 140 µm (P < 0.001 and retinal volume from 12.38 ± 2.1 to 11.53 ± 1.1 mm3 (P < 0.001. No significant differences between the groups were found in two-month BCVA (P = 0.505, two-month central macular thickness (P = 0.660, or two-month retinal volume (P = 0.582.Conclusion: The short-term results of this pilot study

  20. Efficacy of 18F-2-fluoro-2-deoxy-D-glucose Positron Emission Tomography/Computerized Tomography for Bone Marrow Infiltration Assessment in the Initial Staging of Lymphoma

    Directory of Open Access Journals (Sweden)

    Ali Ozan Öner

    2017-06-01

    Full Text Available Objective: Currently 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG positron emission tomography/computerized tomography (PET/CT is being successfully used for staging and follow-up of Hodgkin’s lymphoma (HL and non-Hodgkin’s lymphoma (NHL. Various studies have demonstrated that PET/CT effectively detects bone marrow involvement (BMI and is concordant with bone marrow biopsy (BMB findings, thus it is deemed as a complementary method. This study was aimed to evaluate18F-FDG-PET/CT efficiency for detection of BMI in HL and NHL. Methods: The study included 172 lymphoma cases who were admitted to Akdeniz University Medical School Department of Nuclear Medicine for initial staging with PET/CT. Visual and semiquantitative assessments were performed for PET/CT scan findings of the cases. The maximum standard uptake (SUVmax value was the quantitative parameter used for 18F-FDG-PET scan. In visual assessment, bone marrow metabolic activity that is greater than the liver was considered as pathologic. For semiquantitative assessment, regions of interest were drawn for SUVmax estimation, which included iliac crest in cases with diffusely increased metabolic activity and the highest activity area in cases with focal involvement. BMB was considered as the reference test. Results: On visual assessment of all the cases, PET/CT was found to yield 31% sensitivity and 85% specificity rate for detection of BMI. On visual assessment of HL cases, sensitivity rate was determined as 80%, and specificity as 78%, while in NHL cases the corresponding values were 24% and 90%, respectively. On semiquantitative assessment of HL cases, considering SUVmax≥4, sensitivity was found as 80% and specificity as 68%. In NHL patients, considering SUVmax≥3.2, sensitivity rate was detected as 65% and specificity as 58%. Conclusion: In this study, a moderately high concordance was observed between PET/CT and BMB findings. PET/CT appears to be a significant method for detecting BMI

  1. Impact of contrast exposure from computed tomography angiography on acute kidney injury after neonatal cardiopulmonary bypass surgery.

    Science.gov (United States)

    Carlo, Waldemar F; Clark, Steven T; Borasino, Santiago; Alten, Jeffrey A

    2017-07-01

    Acute kidney injury (AKI) is a frequent complication after cardiopulmonary bypass (CBP) for cardiac surgery in neonates. It is unclear if exposure to computed tomography angiography (CTA) in the preoperative period increases the risk of AKI. We hypothesized a short interval between CTA and CPB surgery would be associated with higher rates of AKI in infants. In this single center retrospective review of patients between 2012 and 2015, neonates less than one month old were analyzed if they had CTA prior to cardiac surgery with CPB. Baseline, demographic, fluid balance, and laboratory data was analyzed. AKI was staged according to KDIGO criteria. Fifty-six neonates were analyzed. AKI developed in 42 (75%) of patients; severe AKI (KDIGO stages 2 and 3) occurred in 18 (32%). Patient characteristics were similar at baseline and at time of CTA between those with and without severe AKI. Patients with severe AKI had longer CPB time, lower postoperative urine output, higher peak serum creatinine, and longer hospital length of stay. When considering intervals between CTA and CPB surgery ≤1 day (n = 19), ≤3 days (n = 28), and >3 days (n = 28); there was no difference in AKI incidence nor postoperative outcomes among these three interval cohorts. Routine exposure to CTA and CPB surgery in close succession does not appear to increase the risk of AKI after neonatal cardiac surgery. Though other risks need to be weighed (eg, sedation, intubation, radiation exposure), this result may enable more liberal utilization of CTA for preoperative surgical planning of congenital heart operations in patients with unclear or complex anatomy. © 2017 Wiley Periodicals, Inc.

  2. Coronary Computed Tomography Angiography: Patient-related factors determining image quality using a second-generation 320-slice CT scanner.

    Science.gov (United States)

    Ghekiere, Olivier; Nchimi, Alain; Djekic, Julien; El Hachemi, Mounia; Mancini, Isabelle; Hansen, Dominique; Vanhoenacker, Piet; de Roos, Albert; Dendale, Paul

    2016-10-15

    To investigate the diagnostic confidence of Coronary Computed Tomography Angiography (CCTA) and the effect of patient-related factors on CCTA image quality using a second-generation 320-slice scanner. 200 consecutive patients (mean age 60±12years; 109 men) prospectively underwent CCTA. The mean body mass index (BMI) was 27.1±4.9kg/m(2); the median heart rate (HR) was 60.0 (interquartile range (IQR), 53.9-66.1) beats per minute (bpm). The median segment's diameter was 2.8 (IQR, 2.2-3.4) mm. For each coronary segment ≥1.5mm in diameter, two readers scored: diameter narrowing as confidence and motion-related image quality, with interobserver agreement kappa-values of 0.89, 0.91 and 0.61 respectively. Seventy-nine of the 2505 evaluated segments (3.2%) had non-diagnostic image quality because of coronary calcifications (66/79; 83.5%), stent- (6/79; 7.5%), pacemaker- (2/79; 2.5%) or motion-related artifacts (5/79; 6.5%). The effect of patient-related factors on motion-related image quality was investigated by multinomial logistic regression in 181 patients with calcium score (IQR, 0-446.5). Increasing coronary diameter was the most improving image quality factor (odds ratio (OR), 1.8637; pimage quality. Using a second-generation 320-slice scanner, CCTA diagnostic confidence is predominantly affected by coronary calcifications, whereas motion-related image quality is non-diagnostic only in exceptional cases and mainly influenced by the coronary diameter. For future developments, our study findings therefore suggest greater requirements concerning spatial resolution and calcium-related artifact removal than concerning temporal resolution, especially to improve diagnostic confidence in patient groups with smaller coronary diameters. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Evaluation of early coronary graft patency after coronary artery bypass graft surgery using multislice computed tomography angiography

    Directory of Open Access Journals (Sweden)

    Raissi Kamal

    2009-12-01

    Full Text Available Abstract Background Coronary artery bypass graft (CABG surgery is the standard of care in the treatment of advanced coronary artery disease, and its long-term results are affected by the failure of bypass grafts. The aim of the present study was to evaluate the early patency rate in coronary bypass grafts. Methods A total of 107 consecutive patients who underwent CABG were included in this study. Early graft patency was evaluated via computed tomography (CT angiography in the first week after surgery. Results There were a total of 366 grafts, comprised of 250 venous grafts and 116 arterial grafts. Multi-slice CT detected acute graft occlusions in 32 (8.7% of all the grafts, including 26 (10% of the 250 venous grafts and 6 (5% of the 116 arterial grafts. The patency rates obtained were 97.3% for the left internal mammary (IMA grafts, 50% for the radial artery grafts, and 50% for the right IMA grafts. Additionally, 107 (96.4% grafts to the left anterior descending artery (LAD were classified as patent, whereas 1 (30% of the 3 grafts in the left circumflex (LCX region and 1 (50% of the 2 grafts in the right coronary artery (RCA territory were found to be occluded. In the venous category, 8 (13.7% of the 58 grafts to LAD were found to be occluded. In the LCX region, 9 (8.5% of the 106 grafts were classified as occluded, while the remaining 97 (91.5% grafts were patent. The venous grafts to RCA were occluded in 9 (10.4% of the 86 grafts. Amongst the multiple preoperative, intraoperative, and postoperative factors, pump time was significantly longer in the patients with occluded grafts than in those with patent grafts (P = 0.04. Conclusion The IMA grafts had the highest early patency rate amongst the coronary bypass grafts. However, the other arterial grafts were associated with a high rate of acute occlusions.

  4. Fusion of morphological data obtained by coronary computed tomography angiography with quantitative echocardiographic data on regional myocardial function.

    Science.gov (United States)

    Lipiec, Piotr; Wejner-Mik, Paulina; Wdowiak-Okrojek, Katarzyna; Szymczyk, Ewa; Skurski, Adam; Napieralski, Andrzej; Kamiński, Marek; Szymczyk, Konrad; Kasprzak, Jarosław D

    2016-01-01

    Three-dimensional (3D) fusion of morphological data obtained by coronary computed tomography angiography (CCTA) with functional data from resting and stress echocardiography could potentially provide additional information compared to examination results analyzed separately and increase the diagnostic and prognostic value of non-invasive imaging in patients with suspected coronary artery disease (CAD). Using vendor-independent software developed in our institution, we aimed to assess the feasibility and reproducibility of 3D fusion of morphological CCTA data with echocardiographic data regarding regional myocardial function. Thirty patients with suspected CAD underwent CCTA and resting transthoracic echocardiography. From CCTA we obtained 3D reconstructions of coronary arteries and left ventricle (LV). Offline speckle-tracking analysis of the echocardiographic images provided parametric maps depicting myocardial longitudinal strain in 17 segments of the LV. Using our software, 3 independent investigators fused echocardiographic maps with CCTA reconstruc-tions in all patients. Based on the obtained fused models, each segment of the LV was assigned to one of the major coronary artery branches. Mean time necessary for data fusion was 65 ± 7 s. Complete agreement between independent investigators in assignment of LV segments to coronary branches was obtained in 94% of the segments. The average coefficient of agreement (kappa) between the investigators was 0.950 and the intra-class correlation coefficient was 0.9329 (95% CI 0.9227-0.9420). Three-dimensional fusion of morphological CCTA data with quantitative echocardiographic data on regional myocardial function is feasible and allows highly repro-ducible assignment of myocardial segments to coronary artery branches.

  5. Increased pre-procedural urinary microalbumin is associated with a risk for renal functional deterioration after coronary computed tomography angiography.

    Science.gov (United States)

    Isobe, Satoshi; Yuba, Miyuki; Mori, Hiroaki; Suzuki, Susumu; Sato, Kimihide; Ishii, Hideki; Murohara, Toyoaki

    2017-03-01

    Urinary microalbumin is a marker for preclinical nephropathy. A percentage change in cystatin C (%CyC) of ≥10% for 24h after tests with contrast media is reportedly an independent predictor for developing contrast-induced nephropathy. We investigated the relationship between the presence of urinary microalbumin and changes in CyC after coronary computed tomography angiography (CCTA). Three hundred and thirty-three patients with known or suspected coronary artery disease who scheduled for CCTA using a 70mL of Iopamidol were enrolled. Serum creatinine and CyC levels were measured at baseline and 24 h post-procedure. The %CyC, absolute changes in estimated glomerular filtration rate (ΔeGFR), and oral fluid volume from pre- to post-procedure were calculated. The patients were dichotomized into 2 groups as follows: group A comprised 83 patients showing a %CyC of ≥10%; and group B comprised 250 patients showing a %CyC of <10%. The ΔeGFR, fasting plasma glucose levels, HbA1c, and pre-procedural urinary microalbumin levels were significantly greater in group A than in group B. Oral fluid intake volume was significantly less in group A than in group B. The urinary microalbumin significantly correlated with %CyC (r=0.504, P<0.0001). Multivariate logistic regression analysis revealed that pre-procedural urinary microalbumin and oral fluid volume were independent predictors for %CyC≥10%. The optimal cut-off value of a pre-procedural urinary microalbumin level was 58mg/g·creatinine for predicting a %CyC≥10% using receiver-operating-characteristic analysis. Renal functional changes should be carefully paid attention to after CCTA, particularly in patients exhibiting increased pre-procedural urinary microablumin levels. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Underuse of risk assessment and overuse of computed tomography pulmonary angiography in patients with suspected pulmonary thromboembolism.

    Science.gov (United States)

    Perera, Michael; Aggarwal, Leena; Scott, Ian A; Cocks, Nicholas

    2017-10-01

    Evidence suggests the potential overuse of computed tomography pulmonary angiography (CTPA) in patients with suspected pulmonary thromboembolism (PTE) in the absence of consistent use of pre-test clinical prediction rules and D-dimer assays. To evaluate use and diagnostic utility of clinical prediction rules and D-dimer assay in patients with suspected PTE and quantify potentially avoidable overuse of CTPA in low risk patients. A total of 344 consecutive patients undergoing CTPA at a tertiary hospital was studied with regards to the use of D-dimer assays and clinical prediction rules for PTE. For each patient, a modified Wells score (mWS), revised Geneva score and PISA model were calculated retrospectively; performance characteristics for each rule for PTE were determined with reference to results of CTPA. Results for the mWS and D-dimer assays (when performed) were used to estimate the overuse of CTPA according to risk category. Use of a clinical prediction rule was documented in only 5.0% of cases. Of 269 low-risk patients who had a calculated mWS ≤4, only 64 (23.8%) had a D-dimer assay performed, with 30 (11.1%) having a PTE on CTPA. Among 75 patients with an mWS >4, 23 (30.7%) had a PTE on CTPA (P 4 had the highest positive predictive value (31.0%) for PTE; all rules demonstrated similar negative predictive values for low-risk scores (87-89%). After adjusting for an 11% false negative rate for PTE in patients with low-risk mWS, overuse of CTPA was reported in up to 190 (55.2%) patients. More than 50% of patients with suspected PTE may be subject to unwarranted use of CTPA in the absence of pre-test clinical prediction rules coupled with D-dimer assays. © 2017 Royal Australasian College of Physicians.

  7. Highly sensitive troponin and coronary computed tomography angiography in the evaluation of suspected acute coronary syndrome in the emergency department.

    Science.gov (United States)

    Ferencik, Maros; Hoffmann, Udo; Bamberg, Fabian; Januzzi, James L

    2016-08-07

    The evaluation of patients presenting to the emergency department with suspected acute coronary syndrome (ACS) remains a clinical challenge. The traditional assessment includes clinical risk assessment based on cardiovascular risk factors with serial electrocardiograms and cardiac troponin measurements, often followed by advanced cardiac testing as inpatient or outpatient (i.e. stress testing, imaging). Despite this costly and lengthy work-up, there is a non-negligible rate of missed ACS with an increased risk of death. There is a clinical need for diagnostic strategies that will lead to rapid and reliable triage of patients with suspected ACS. We provide an overview of the evidence for the role of highly sensitive troponin (hsTn) in the rapid and efficient evaluation of suspected ACS. Results of recent research studies have led to the introduction of hsTn with rapid rule-in and rule-out protocols into the guidelines. Highly sensitive troponin increases the sensitivity for the detection of myocardial infarction and decreases time to diagnosis; however, it may decrease the specificity, especially when used as a dichotomous variable, rather than continuous variable as recommended by guidelines; this may increase clinician uncertainty. We summarize the evidence for the use of coronary computed tomography angiography (CTA) as the rapid diagnostic tool in this population when used with conventional troponin assays. Coronary CTA significantly decreases time to diagnosis and discharge in patients with suspected ACS, while being safe. However, it may lead to increase in invasive procedures and includes radiation exposure. Finally, we outline the opportunities for the combined use of hsTn and coronary CTA that may result in increased efficiency, decreased need for imaging, lower cost, and decreased radiation dose. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  8. Optical coherence tomography angiography vessel density mapping at various retinal layers in healthy and normal tension glaucoma eyes.

    Science.gov (United States)

    Shin, Joong Won; Sung, Kyung Rim; Lee, Ji Yun; Kwon, Junki; Seong, Mincheol

    2017-06-01

    To investigate peripapillary vessel density at various spatial locations and layers in healthy and normal tension glaucoma eyes using optical coherence tomography angiography (OCTA). A commercial OCTA device (AngioPlex; Carl Zeiss Meditec) was used to image microvasculature in a 6 × 6-mm optic disc region. Vessel densities of superficial and deep retinal layers were calculated using an automatic thresholding algorithm. Vessel density maps were plotted by averaging individual angiogram images. The spatial characteristics of vessel densities were analyzed at clock-hour sectors and in five 0.7-mm-thick concentric circles from a diameter of 2.0 to 5.5 mm. Areas under the receiver operating characteristics curves (AUCs) assessed the glaucoma diagnostic ability. Vessel density maps of superficial and deep retinal layers were significantly reduced at the 7 and 11 o'clock positions in glaucomatous eyes. In superficial layer, vessel density significantly decreased as the distance from the optic disc margin increased, except in the innermost circle (2.0-2.7-mm). There were significant differences in AUCs of superficial vessel density between innermost circle and the other outer circles. In the deep layer, the innermost circle showed significantly higher vessel density than the outer circles. Vessel density at 7 o'clock showed the best diagnostic performance (AUCs, 0.898 and 0.789) both in the superficial and deep layers. The innermost circle showed eccentric feature compared to the outer circles in terms of spatial characteristics and diagnostic ability. Understanding of the spatial characteristics of peripapillary vasculature may be helpful in clinical practice and determining the optimal measurement area of vessel density.

  9. The effect of blood pressure on non-invasive fractional flow reserve derived from coronary computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Akira [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Coenen, Adriaan; Lubbers, Marisa M.; Nieman, Koen [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Erasmus University Medical Center, Departmenet of Cardiology, Rotterdam (Netherlands); Kido, Teruhito; Mochizuki, Teruhito [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Kido, Tomoyuki [Matsuyama Saiseikai Hospital, Department of Radiology, Matsuyama, Ehime (Japan); Yamashita, Natsumi [Clinical Research Center, National Hospital Organization Shikoku Cancer Center, Division of Clinical Biostatistics, Section of Cancer Prevention and Epidemiology, Matsuyama, Ehime (Japan); Watanabe, Kouki [Matsuyama Saiseikai Hospital, Department of Cardiology, Matsuyama, Ehime (Japan); Krestin, Gabriel P. [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands)

    2017-04-15

    The aim of this study is to assess the effect of blood pressure (BP) on coronary computed tomography angiography (CTA) derived computational fractional flow reserve (CTA-FFR). Twenty-one patients who underwent coronary CTA and invasive FFR were retrospectively identified. Ischemia was defined as invasive FFR ≤0.80. Using a work-in-progress computational fluid dynamics algorithm, CTA-FFR was computed with BP measured before CTA, and simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg respectively. Correlation between CTA-FFR and invasive FFR was assessed using Pearson test. The repeated measuring test was used for multiple comparisons of CTA-FFR values by simulated BP inputs. Twenty-nine vessels (14 with invasive FFR ≤0.80) were assessed. The average CTA-FFR for measured BP (134 ± 20/73 ± 12 mmHg) was 0.77 ± 0.12. Correlation between CTA-FFR by measured BP and invasive FFR was good (r = 0.735, P < 0.001). For simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg, the CTA-FFR increased: 0.69 ± 0.13, 0.73 ± 0.12, 0.75 ± 0.12, 0.77 ± 0.11, 0.79 ± 0.11, and 0.81 ± 0.10 respectively (P < 0.05). Measurement of the BP just before CTA is preferred for accurate CTA-FFR simulation. BP variations in the common range slightly affect CTA-FFR. However, inaccurate BP assumptions differing from the patient-specific BP could cause misinterpretation of borderline significant lesions. (orig.)

  10. Analysis and follow-up of type 1 choroidal neovascularisation with optical coherence tomography-angiography after antiangiogenic treatment.

    Science.gov (United States)

    Torrecillas-Picazo, R; Cerdà-Ibáñez, M; Almor Palacios, I; Hervás Hernandis, J M; Ramón-Cosín, R; Ruiz Del Rio, N; Duch-Samper, A

    2017-06-01

    To describe the characteristics of type 1 choroidal neovascularisation (CNV) in age-related macular degeneration (ARMD) using two different optical coherence tomography angiography (OCT-A) devices sequentially during a standard protocol of three intravitreal injections of an anti-vascular endothelial growth factor (anti-VEGF). The study included 6 eyes with naïve neovascular ARMD. Macular OCT-A images were acquired using AngioPlex Cirrus HD-OCT 5000 (Carl Zeiss Meditec, Inc., Dublin, USA) and DRI OCT Triton SS-OCT Angio (Topcon, Medical Systems, Inc. Oakland, NJ, USA). The macular OCT-A scan covered an area of 3×3mm. Distinct morphological patterns and quantifiable features of the neovascular membranes were studied on en face projection images, which were taken at different stages of the follow-up. Treatment response could be estimated using the OCT-A criteria of CNV activity. Higher activity scores before treatment resulted in a greater decrease in the membrane area. The estimated net decline in area ranged from 83.5% to 1.4%. The OCT-A performed one-week after treatment revealed the greatest area reductions. OCT-A provides new possibilities for the non-invasive assessment of features of neovascular networks and CNV structural morphology. Newly described activity criteria can also guide therapeutic decisions, and help in evaluating responses. Quantitative and qualitative information can be provided with this technique. However, further software development and future investigation are essential to define the role of this tool on a daily basis. Copyright © 2017 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. Lower extremity computed tomography angiography can help predict technical success of endovascular revascularization in the superficial femoral and popliteal artery.

    Science.gov (United States)

    Itoga, Nathan K; Kim, Tanner; Sailer, Anna M; Fleischmann, Dominik; Mell, Matthew W

    2017-09-01

    Preprocedural computed tomography angiography (CTA) assists in evaluating vascular morphology and disease distribution and in treatment planning for patients with lower extremity peripheral artery disease (PAD). The aim of the study was to determine the predictive value of radiographic findings on CTA and technical success of endovascular revascularization of occlusions in the superficial femoral artery-popliteal (SFA-pop) region. Medical records and available imaging studies were reviewed for patients undergoing endovascular intervention for PAD between January 2013 and December 2015 at a single academic institution. Radiologists reviewed preoperative CTA scans of patients with occlusions in the SFA-pop region. Radiographic criteria previously used to evaluate chronic occlusions in the coronary arteries were used. Technical success, defined as restoration of inline flow through the SFA-pop region with technical failure (P = .014). Longer lengths of occlusion were also associated with technical failure (P = .042). Multiple occlusions (P = .55), negative remodeling (P = .69), vessel runoff (P = .56), and percentage of vessel calcification (P = .059) were not associated with failure. On multivariable analysis, 100% calcification remained the only significant predictor of technical failure (odds ratio, 9.0; 95% confidence interval, 1.8-45.8; P = .008). Analysis of preoperative CTA shows 100% calcification as the best predictor of technical failure of endovascular revascularization of occlusions in the SFA-pop region. Further studies are needed to determine the cost-effectiveness of obtaining preoperative CTA for lower extremity PAD. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  12. Assessment of left ventricular function and mass in dual-source computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Christoph J., E-mail: c.jensen@contilia.d [Department of Cardiology and Angiology, Elisabeth Hospital, Essen (Germany); Jochims, Markus [Department of Cardiology and Angiology, Elisabeth Hospital, Essen (Germany); Hunold, Peter; Forsting, Michael; Barkhausen, Joerg [Department of Diagnostic and Interventional Radiology and Neuroradiology, University of Essen (Germany); Sabin, Georg V.; Bruder, Oliver [Department of Cardiology and Angiology, Elisabeth Hospital, Essen (Germany); Schlosser, Thomas [Department of Diagnostic and Interventional Radiology and Neuroradiology, University of Essen (Germany)

    2010-06-15

    Purpose: To quantify left ventricular (LV) function and mass (LVM) derived from dual-source computed tomography (DSCT) and the influence of beta-blocker administration compared to cardiac magnetic resonance imaging (CMR). Methods: Thirty-two patients undergoing cardiac DSCT and CMR were included, where of fifteen received metoprolol intravenously before DSCT. LV parameters were calculated by the disc-summation method (DSM) and by a segmented region-growing algorithm (RGA). All data sets were analyzed by two blinded observers. Interobserver agreement was tested by the intraclass correlation coefficient. Results.: 1. Using DSM LV parameters were not statistically different between DSCT and CMR in all patients (DSCT vs. CMR: EF 63 {+-} 8% vs. 64 {+-} 8%, p = 0.47; EDV 136 {+-} 36 ml vs. 138 {+-} 35 ml, p = 0.66; ESV 52 {+-} 21 ml vs. 52 {+-} 22 ml, p = 0.61; SV 83 {+-} 22 ml vs. 87 {+-} 19 ml, p = 0.22; CO 5.4 {+-} 0.9 l/min vs. 5.7 {+-} 1.2 l/min, p = 0.09, LVM 132 {+-} 33 g vs. 132 {+-} 33 g, p = 0.99). 2. In a subgroup of 15 patients beta-blockade prior to DSCT resulted in a lower ejection fraction (EF), stroke volume (SV), cardiac output (CO) and increase in end systolic volume (ESV) in DSCT (EF 59 {+-} 8% vs. 62 {+-} 9%; SV 73 {+-} 17 ml vs. 81 {+-} 15 ml; CO 5.7 {+-} 1.2 l/min vs. 5.0 {+-} 0.8 l/min; ESV 52 {+-} 27 ml vs. 57 {+-} 24 ml, all p < 0.05). 3. Analyzing the RGA parameters LV volumes were not significantly different compared to DSM, whereas LVM was higher using RGA (177 {+-} 31 g vs. 132 {+-} 33 g, p < 0.05). Interobserver agreement was excellent comparing DSM values with best agreement between RGA calculations. Conclusion: Left ventricular volumes and mass can reliably be assessed by DSCT compared to CMR. However, beta-blocker administration leads to statistically significant reduced EF, SV and CO, whereas ESV significantly increases. DSCT RGA reliably analyzes LV function, whereas LVM is overestimated compared to DSM.

  13. Computed tomography angiography of lower extremities in the emergency room for evaluation of patients with gunshot wounds

    Energy Technology Data Exchange (ETDEWEB)

    Adibi, Ali; Plotnik, Adam N.; Mohajer, Kiyarash; Arellano, Cesar; Ruehm, Stefan G. [University of California, Diagnostic Cardiovascular Imaging, Department of Radiological Sciences, Los Angeles, CA (United States); Krishnam, Mayil S.; Dissanayake, Sumudu [University of California, Cardiovascular and Thoracic Imaging, Department of Radiology, Irvine, CA (United States)

    2014-07-15

    To assess the role of CT angiography in the evaluation of patients with lower extremity gunshot wounds in the emergency room. Eighty patients (73 male, 7 female, mean age 26 years) underwent CT angiography for the evaluation of lower extremity gunshot injuries. Imaging was conducted on the basis of standardized protocols utilizing 16-slice and 64-slice multidetector systems and images were qualitatively graded and assessed for various forms of arterial injury. CT angiography findings indicative of arterial injury were observed in 24 patients (30 %) and a total of 43 arterial injuries were noted; the most common form was focal narrowing/spasm (n = 16, 37.2 %); the most common artery involved was the superficial femoral artery (n = 12, 50 %). In qualitative assessment of images based on a 4-point grading system, both readers considered CT angiography diagnostically excellent (grade 4) in most cases. Surgical findings were consistent with CT angiography and follow-up of patients' medical records showed no arterial injuries in patients with normal findings on initial imaging. Our findings demonstrate that CT angiography is an effective imaging modality for evaluation of lower extremity gunshot wounds and could help limit more invasive procedures such as catheter angiography to a select group of patients. (orig.)

  14. Diagnostic performance of coronary CT angiography, stress dual-energy CT perfusion, and stress perfusion single-photon emission computed tomography for coronary artery disease: Comparison with combined invasive coronary angiography and stress perfusion cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyun Woo; Ko, Sung Min; Hwang, Hweung Kon; So, Young; Yi, Jeong Geun [Konkuk University Medical Center, Research Institute of Biomedical Science, Konkuk University School of Medicine, Seoul (Korea, Republic of); Lee, Eun Jeong [Dept. of Nuclear Medicine, Seoul Medical Center, Seoul (Korea, Republic of)

    2017-06-15

    To investigate the diagnostic performance of coronary computed tomography angiography (CCTA), stress dual-energy computed tomography perfusion (DE-CTP), stress perfusion single-photon emission computed tomography (SPECT), and the combinations of CCTA with myocardial perfusion imaging (CCTA + DE-CTP and CCTA + SPECT) for identifying coronary artery stenosis that causes myocardial hypoperfusion. Combined invasive coronary angiography (ICA) and stress perfusion cardiac magnetic resonance (SP-CMR) imaging are used as the reference standard. We retrospectively reviewed the records of 25 patients with suspected coronary artery disease, who underwent CCTA, DE-CTP, SPECT, SP-CMR, and ICA. The reference standard was defined as ≥ 50% stenosis by ICA, with a corresponding myocardial hypoperfusion on SP-CMR. For per-vascular territory analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 96, 96, 68, 93, and 68%, respectively, and specificities were 72, 75, 89, 85, and 94%, respectively. The areas under the receiver operating characteristic curve (AUCs) were 0.84 ± 0.05, 0.85 ± 0.05, 0.79 ± 0.06, 0.89 ± 0.04, and 0.81 ± 0.06, respectively. For per-patient analysis, the sensitivities of CCTA, DE-CTP, SPECT, CCTA + DE-CTP, and CCTA + SPECT were 100, 100, 89, 100, and 83%, respectively; the specificities were 14, 43, 57, 43, and 57%, respectively; and the AUCs were 0.57 ± 0.13, 0.71 ± 0.11, 0.73 ± 0.11, 0.71 ± 0.11, and 0.70 ± 0.11, respectively. The combination of CCTA and DE-CTP enhances specificity without a loss of sensitivity for detecting hemodynamically significant coronary artery stenosis, as defined by combined ICA and SP-CMR.

  15. Some aspects of evaluation of image quality in computerized tomography; Alguns aspectos da avaliacao da qualidade da imagem em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Travassos, Paulo Cesar Baptista; Peixoto, Jose Guilherme; Almeida, Carlos Eduardo Veloso de, E-mail: pctravassos@gmail.com [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Campos, Luciana Tourinho; Magalhaes, Luis Alexandre [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    The evaluation of CT scanners image quality includes measuring the Hounsfield values, HU, using a table with the limit values. This table does not consider that different devices have different effective energies, which may cause some false results. The evaluation of 90 computerized tomography, by the American College Radiology methodology, showed that some failed devices in the evaluation showed excellent linear fit between the values of the linear attenuation coefficients calculated for the actual energy used, according to the HU values. The analysis of the coefficient of determination suggests that 10 of these devices could have been approved. (author)

  16. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Carlier, Stéphane, E-mail: sgcarlier@hotmail.com [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Didday, Rich [INDEC Medical Systems Inc., Santa Clara, CA (United States); Slots, Tristan [Pie Medical Imaging BV, Maastricht (Netherlands); Kayaert, Peter; Sonck, Jeroen [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); El-Mourad, Mike; Preumont, Nicolas [Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Schoors, Dany; Van Camp, Guy [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium)

    2014-06-15

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization.

  17. Normal values of regional left ventricular myocardial thickness, mass and distribution-assessed by 320-detector computed tomography angiography in the Copenhagen General Population Study

    DEFF Research Database (Denmark)

    Hindsø, Louise; Fuchs, Andreas; Kühl, Jørgen Tobias

    2017-01-01

    Left ventricular (LV) hypertrophy is associated with cardiovascular complications and the geometry is important for prognosis. In some cardiovascular diseases, myocardial hypertrophy or dilation occurs regionally without modifying the global size of the heart. It is therefore relevant to determine...... regional normal reference values of the left ventricle. The aim of this study was to derive reference values of regional LV myocardial thickness (LVMT) and mass (LVMM) from a healthy study group of the general population using cardiac computed tomography angiography (CCTA). We wanted to introduce LV...

  18. Quantification of Soil Physical Properties by Using X-Ray Computerized Tomography (CT) and Standard Laboratory (STD) Methods

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Maria Ambert [Iowa State Univ., Ames, IA (United States)

    2003-12-12

    The implementation of x-ray computerized tomography (CT) on agricultural soils has been used in this research to quantify soil physical properties to be compared with standard laboratory (STD) methods. The overall research objective was to more accurately quantify soil physical properties for long-term management systems. Two field studies were conducted at Iowa State University's Northeast Research and Demonstration Farm near Nashua, IA using two different soil management strategies. The first field study was conducted in 1999 using continuous corn crop rotation for soil under chisel plow with no-till treatments. The second study was conducted in 2001 and on soybean crop rotation for the same soil but under chisel plow and no-till practices with wheel track and no-wheel track compaction treatments induced by a tractor-manure wagon. In addition, saturated hydraulic (K{sub s}) conductivity and the convection-dispersion (CDE) model were also applied using long-term soil management systems only during 2001. The results obtained for the 1999 field study revealed no significant differences between treatments and laboratory methods, but significant differences were found at deeper depths of the soil column for tillage treatments. The results for standard laboratory procedure versus CT method showed significant differences at deeper depths for the chisel plow treatment and at the second lower depth for no-till treatment for both laboratory methods. The macroporosity distribution experiment showed significant differences at the two lower depths between tillage practices. Bulk density and percent porosity had significant differences at the two lower depths of the soil column. The results obtained for the 2001 field study showed no significant differences between tillage practices and compaction practices for both laboratory methods, but significant differences between tillage practices with wheel track and no-wheel compaction treatments were found along the soil

  19. Investigating the effect of characteristic x-rays in cadmium zinc telluride detectors under breast computerized tomography operating conditions.

    Science.gov (United States)

    Glick, Stephen J; Didier, Clay

    2013-10-14

    A number of research groups have been investigating the use of dedicated breast computerized tomography (CT). Preliminary results have been encouraging, suggesting an improved visualization of masses on breast CT as compared to conventional mammography. Nonetheless, there are many challenges to overcome before breast CT can become a routine clinical reality. One potential improvement over current breast CT prototypes would be the use of photon counting detectors with cadmium zinc telluride (CZT) (or CdTe) semiconductor material. These detectors can operate at room temperature and provide high detection efficiency and the capability of multi-energy imaging; however, one factor in particular that limits image quality is the emission of characteristic x-rays. In this study, the degradative effects of characteristic x-rays are examined when using a CZT detector under breast CT operating conditions. Monte Carlo simulation software was used to evaluate the effect of characteristic x-rays and the detector element size on spatial and spectral resolution for a CZT detector used under breast CT operating conditions. In particular, lower kVp spectra and thinner CZT thicknesses were studied than that typically used with CZT based conventional CT detectors. In addition, the effect of characteristic x-rays on the accuracy of material decomposition in spectral CT imaging was explored. It was observed that when imaging with 50-60 kVp spectra, the x-ray transmission through CZT was very low for all detector thicknesses studied (0.5-3.0 mm), thus retaining dose efficiency. As expected, characteristic x-ray escape from the detector element of x-ray interaction increased with decreasing detector element size, approaching a 50% escape fraction for a 100 μm size detector element. The detector point spread function was observed to have only minor degradation with detector element size greater than 200 μm and lower kV settings. Characteristic x-rays produced increasing distortion

  20. [Aging changes of the root canal morphology in maxillary first premolars observed by cone-beam computerized tomography].

    Science.gov (United States)

    Hu, R C; Cao, L L; Xie, W; Hu, Y Q; Piao, Z G

    2016-04-09

    To observe the morphological changes of root canals with aging in maxillary first premolars by using cone-beam computerized tomography(CBCT)in order to facilitate endodontic management of root canals in various aged patients. The digital CBCT data of the maxillary first premolars in 405 cases from the patients in Oral Medical Center of The First Affiliated Hospital, Jinan University from March 2011 to June 2015 were collected. The CBCT images were divided into 6 groups according to the patients' ages: groups 11-20, 21-30, 31-40, 41-50, 51-60 and >60 years-olds, respectively. Changes of morphologies of root canals with aging including such parameters as types of the root canal, incidence of double root canals in single rooted teeth, distance between both root canal orifices of double rooted canals, and morphological change of the cross section of roots. Chi-square test and liner trend test were adopted in statistical analysis in the present study. The distribution of various types of the root canals were significantly different amongst various aged groups(Paging, the percentages of type Ⅰ and type Ⅲ decreased while type Ⅱ increased. However, there were no remarkable changes of type Ⅳ observed. The incidence of double rooted canals in single rooted teeth gradually increased with aging especially in 20-years-old and above groups, e.g. 51.7%(31/60)in group 11-20 years-olds and 83.0%(44/53)in group 21-30 years-olds. However, there was no significant increase observed after the age of 40. The distance between both root canal orifices of double rooted canals became shorter with aging except in groups of 40-years-olds and above. The morphologies of the cross sections in most aged groups were flat shaped(1 020/2 105, 48.5%)and oval shape(594/2 105, 28.2%). Along with aging, the percentage of circular shape gradually increased while flat and oval shapes decreased. The morphology of root canal could be clearly showed by the CBCT images. The change of morphologies of

  1. Low-dose, prospective triggered high-pitch spiral coronary computed tomography angiography: comparison with retrospective spiral technique.

    NARCIS (Netherlands)

    Srichai, M.B.; Lim, R.P.; Donnino, R.; Mannelli, L.; Hiralal, R.; Avery, R.; Ho, C.; Babb, J.S.; Jacobs, J.E.

    2012-01-01

    RATIONALE AND OBJECTIVES: Cardiac computed tomographic angiography algorithms emphasize radiation reduction while maintaining diagnostic image quality (IQ). The aim of this study was to evaluate IQ and interreader variability using prospective electrocardiographically triggered high-pitch spiral

  2. The use of computerized tomography in pediatrics: risk of radiation; Actualizacion de temas relacionados con elriesgo de radiacion y la obtencion de imagenes pediatricas por tomografia computerizada

    Energy Technology Data Exchange (ETDEWEB)

    Lane, F.; Donnelly, M. D.

    2004-07-01

    The use of computerized tomography in paediatrics is rapidly increasing and with that the dose received by the patients. Recent publications show that the new technique is overused and therefore the cancer risk is increasing in paediatric patients. The article discusses the strategies in use ro reduce the radiation doses without losing the advantages of the new technique. Paediatric doses can be reduced adjusting the photon beam to the density and dimensions of the paediatric patient, in new equipment modulating automatically the current and the tension in the cathodic tube to the optimum values without impairing the quality of the image. Dose can also be reduce increasing the rotation velocity and the pitch of the gantry, limiting the exploration to the region of interest and using shielding to protect the most sensitive tissues. Nevertheless, the article defends the prudent use of computerised tomography and recommends, whenever possible, the use of complementary non ionizing radiation techniques. (Author) 26 refs.

  3. 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.

  4. The Quantitative Measurements of Vascular Density and Flow Areas of Macula Using Optical Coherence Tomography Angiography in Normal Volunteers.

    Science.gov (United States)

    Ghassemi, Fariba; Fadakar, Kaveh; Bazvand, Fatemeh; Mirshahi, Reza; Mohebbi, Masoumeh; Sabour, Siamak

    2017-06-01

    The quantification of the density of macular vascular networks and blood flow areas in the foveal and parafoveal area in healthy subjects using optical coherence tomography angiography (OCTA). Cross-sectional, prospective study in an institutional setting at the Retina Services of Farabi Eye Hospital. One hundred twelve normal volunteers with no known ocular or systemic disease were included, including patient numbers (one or both eyes), selection procedures, inclusion/exclusion criteria, randomization procedure, and masking. En face angiogram OCTA was performed on a 3 mm × 3 mm region centered on the macula. Automated thresholding and measuring algorithm method for foveal and parafoveal blood flow and vascular density (VD) were used. The density of macular vascular networks and blood flow area in the foveal and parafoveal area were measured. A total of 224 healthy eyes from 112 subjects with a mean age of 36.4 years ± 11.3 years were included. In the foveal region, the VD of the superficial capillary network (sCN) was significantly higher than that of the deep capillary network (dCN) (31.1% ± 5.5% vs. 28.3% ± 7.2%; P < .001), whereas in the parafoveal area, VD was higher in the dCN (62.24% ± 2.8% vs. 56.5% ± 2.5%; P < .001). Flow area in the 1-mm radius circle in the sCN was less than in the dCN. Superficial foveal avascular zone (sFAZ) size was negatively correlated with the VD of the foveal sCN, but in the deep FAZ (dFAZ) was not correlated with VD or blood flow area of the fovea. There was no difference between measured VD and blood flow surface area in both eyes of the subjects. OCTA could be used as a noninvasive, repeatable, layer-free method in quantitative evaluation of VD and blood flow of macular area. The normal quantities of the vascular plexus density and flow will help in better understanding the pathophysiological basis of the vascular disease of retina. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:478-486.]. Copyright 2017, SLACK

  5. Comparison of C-arm Computed Tomography and Digital Subtraction Angiography in Patients with Chronic Thromboembolic Pulmonary Hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Hinrichs, Jan B., E-mail: hinrichs.jan@mh-hannover.de; Marquardt, Steffen, E-mail: marquardt.steffen@mh-hannover.de; Falck, Christian von, E-mail: falck.christian.von@mh-hannover.de [Hannover Medical School, Department for Diagnostic and Interventional Radiology, German Center for Lung Research (DZL) (Germany); Hoeper, Marius M., E-mail: hoeper.marius@mh-hannover.de; Olsson, Karen M., E-mail: olsson.karen@mh-hannover.de [Hannover Medical School, Clinic for Pneumology, German Center for Lung Research (DZL) (Germany); Wacker, Frank K., E-mail: wacker.frank@mh-hannover.de; Meyer, Bernhard C., E-mail: meyer.bernhard@mh-hannover.de [Hannover Medical School, Department for Diagnostic and Interventional Radiology, German Center for Lung Research (DZL) (Germany)

    2016-01-15

    PurposeTo assess the feasibility and diagnostic performance of contrast-enhanced, C-arm computed tomography (CACT) of the pulmonary arteries compared to digital subtraction angiography (DSA) in patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH).MaterialsFifty-two patients with CTEPH underwent ECG-gated DSA and contrast-enhanced CACT. Two readers (R1, R2) independently evaluated pulmonary artery segments and their sub-segmental branching using DSA and CACT for optimal image quality. Afterwards, the diagnostic findings, i.e., intraluminal filling defects, stenosis, and occlusion, were compared. Inter-modality and inter-observer agreement was calculated, and subsequently consensus reading was done and correlated to a reference standard representing the overall consensus of both modalities. Fisher’s exact test and Cohen’s Kappa were applied.ResultsA total of 1352 pulmonary segments were evaluated, of which 1255 (92.8 %) on DSA and 1256 (92.9 %) on CACT were rated to be fully diagnostic. The main causes of the non-diagnostic image quality were motion artifacts on CACT (R1:37, R2:78) and insufficient contrast enhancement on DSA (R1:59, R2:38). Inter-observer agreement was good for DSA (κ = 0.74) and CACT (κ = 0.75), while inter-modality agreement was moderate (R1: κ = 0.46, R2: κ = 0.47). Compared to the reference standard, the inter-modality agreement for CACT was excellent (κ = 0.96), whereas it was inferior for DSA (κ = 0.61) due to the higher number of abnormal consensus findings read as normal on DSA.ConclusionCACT of the pulmonary arteries is feasible and provides additional information to DSA. CACT has the potential to improve the diagnostic work-up of patients with CTEPH and may be particularly useful prior to surgical or interventional treatment.

  6. Prevalence of Coronary Artery Intramyocardial Course in a Large Population of Clinical Patients Detected by Multislice Computed Tomography Coronary Angiography

    Energy Technology Data Exchange (ETDEWEB)

    De Rosa, R.; Sacco, M.; Tedeschi, C.; Pepe, R.; Capogrosso, P.; Montemarano, E.; Rotondo, A.; Runza, G.; Midiri, M.; Cademartiri, F. (UO di Radiologia, Ospedale San Gennaro, Napoli (Italy))

    2008-10-15

    Background: Intramyocardial course, an inborn coronary anomaly, is defined as a segment of a major epicardial coronary artery that runs intramurally through the myocardium; in particular, we distinguish myocardial bridging, in which the vessel returns to an epicardial position after the muscle bridge, and intramyocardial course, which is described as a vessel running and ending in the myocardium. Purpose: To evaluate the prevalence of myocardial bridging and intramyocardial course of coronary arteries as defined by multidetector computed tomography (MDCT) angiography. Material and Methods: The study population consisted of 242 consecutive patients (211 men, 31 women; mean age 59+-6 years) with atypical chest pain admitted to our hospital between December 2004 and September 2006. All MDCT examinations were performed using a 16-detector-row scanner (Aquilion 16 CFX; Toshiba Medical System, Tokyo, Japan). Patients with heart rate above 65 bpm received 50 mg atenolol orally for 3 days prior to the MDCT scan, or they increased their usual therapy with beta-blockers, in order to obtain a prescan heart rate <60 bpm. Curved multiplanar and 3D volume reconstructions were performed to explore coronary anatomy. Results: In 235 patients, the CT scan was successful and images were appropriate for evaluation. The prevalence of myocardial bridging and intramyocardial course of coronary arteries was 18.7% (47 cases) in our patient population. In 30 segments (63.8%), the vessels ran and ended in the myocardium. In the remaining 17 segments (36.2%), the vessels returned to an epicardial position after the muscle bridge. We found no difference in the prevalence of this inborn coronary anomaly when comparing different clinical characteristics of the study population (sex, age, body-mass index [BMI], etc.). The mean length of the subepicardial artery was 7 mm (range 5-12 mm), and the mean depth in the diastolic phase was 1.9 mm (range 1.2-2.3 mm). There was no significant difference of

  7. Ventilation/Perfusion SPECT lung scintigraphy and computed tomography pulmonary angiography in patients with clinical suspicion of pulmonary embolism.

    Science.gov (United States)

    Ibáñez-Bravo, S; Banzo, I; Quirce, R; Martínez-Rodríguez, I; Jiménez-Bonilla, J; Martínez-Amador, N; Parra, J A; González-Macías, J; Carril, J M

    2016-01-01

    The aim was to compare ventilation/perfusion SPECT lung scintigraphy (V/Q-SPECT) and computed tomography pulmonary angiography (CTPA) in patients with suspicion of pulmonary embolism (PE). This prospectively designed study included 53 patients with intermediate or high clinical probability of PE. A V/Q-SPECT and CTPA was performed on all patients. The V/Q-SPECT was interpreted according to the European Association of Nuclear Medicine and Molecular Imaging (EANMMI) guidelines. CTPA was reported as positive, negative, or indeterminate. CTPA was positive in 22 cases, negative in 28, and indeterminate in 3. V/Q-SPECT was positive in 27 cases, negative in 24, and non-diagnostic in 2. In the 22 with positive CTPA, V/Q-SPECT was positive in 18, negative in 3, and non-diagnostic in 1. In the 28 with negative CTPA, V/Q-SPECT was positive in 8, negative in 19, and non-diagnostic in 1. In the 3 with indeterminate CTPA, V/Q-SPECT was positive in 1 and negative in 2. In the 2 non-diagnostic cases V/Q-SPECT, CTPA was positive in 1 and negative in one. In the 10 high clinical probabilities, CTPA and V/Q-SPECT were positive in 7, negative in 2, and in 1, CTPA was positive and V/Q-SPECT negative. In the 38 intermediate probability group, CTPA and V/Q-SPECT were positive in 11, negative in 17, with CTPA negative and V/Q-SPECT positive in 8, and in 2 CTPA was positive and V/Q-SPECT negative. The results show that V/Q-SPECT detected PE in 5 patients more than CTPA. Our results show a 77% concordance of both techniques. Overall V/Q-SPECT detected PE in 18% more patients than CTPA in the intermediate group. Both techniques have a complementary role when a diagnosis cannot be made with one of them. Copyright © 2016 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  8. Improving Image Quality of Coronary Computed Tomography Angiography Using Patient Weight and Height-Dependent Scan Trigger Threshold.

    Science.gov (United States)

    Kang, Deqiang; Hua, Haiqin; Peng, Nan; Zhao, Jing; Wang, Zhiqun

    2017-04-01

    We aim to improve the image quality of coronary computed tomography angiography (CCTA) by using personalized weight and height-dependent scan trigger threshold. This study was divided into two parts. First, we performed and analyzed the 100 scheduled CCTA data, which were acquired by using body mass index-dependent Smart Prep sequence (trigger threshold ranged from 80 Hu to 250 Hu based on body mass index). By identifying the cases of high quality image, a linear regression equation was established to determine the correlation among the Smart Prep threshold, height, and body weight. Furthermore, a quick search table was generated for weight and height-dependent Smart Prep threshold in CCTA scan. Second, to evaluate the effectiveness of the new individual threshold method, an additional 100 consecutive patients were divided into two groups: individualized group (n = 50) with weight and height-dependent threshold and control group (n = 50) with the conventional constant threshold of 150 HU. Image quality was compared between the two groups by measuring the enhancement in coronary artery, aorta, left and right ventricle, and inferior vena cava. By visual inspection, image quality scores were performed to compare between the two groups. Regression equation between Smart Prep threshold (K, Hu), height (H, cm), and body weight (BW, kg) was K = 0.811 × H + 1.917 × BW - 99.341. When compared to the control group, the individualized group presented an average overall increase of 12.30% in enhancement in left main coronary artery, 12.94% in proximal right coronary artery, and 10.6% in aorta. Correspondingly, the contrast-to-noise ratios increased by 26.03%, 27.08%, and 23.17%, respectively, and by 633.1% in contrast between aorta and left ventricle. Meanwhile, the individualized group showed an average overall decrease of 22.7% in enhancement of right ventricle and 32.7% in inferior vena cava. There was no significant difference of the

  9. Risk classification of highly sensitive troponin I predict presence of vulnerable plaque assessed by dual source coronary computed tomography angiography.

    Science.gov (United States)

    Liu, Ting; Wang, Guan; Li, Peiling; Dai, Xu

    2017-11-01

    Patients presenting to the emergency department with acute chest pain, negative conventional troponin and electrocardiogram require serial testing to rule out acute coronary syndrome (ACS). We studied the association of highly sensitive troponin (hsTn) I with vulnerable plaque features as detected by coronary dual source computed tomography angiography (DSCTA) and determined whether hsTn I at the time of presentation combined with early DSCTA could improve classification of patients as high-risk or low risk for ACS. We included 220 patients with acute chest pain, negative electrocardiogram and conventional troponin who underwent DSCTA and had hsTn I measured at the time of presentation. The patients were categorized as having hsTn I below the limit of detection (low risk), intermediate and above the 99th percentile (high risk). Readers assessed DSCTA qualitatively for the presence of significant CAD (≥50% stenosis), calcified and non-calcified coronary plaque, and vulnerable plaque features (positive remodeling, low CT attenuation plaque, napkin-ring sign, spotty calcium). The mean age of the population was 50.3 ± 8.2 years (43% women). ACS during the index hospitalization occurred in 36 (16.3%) patients (myocardial infarction n = 8, unstable angina pectoris n = 28). HsTn I was below the limit of detection, intermediate, and above 99th percentile in 39 (17.7%), 139 (86.9%), and 42 (19.1%) patients, respectively. Across the categories of low risk, intermediate and high risk of hsTn I, there was increase in prevalence of ≥50% stenosis (0, 11.5, and 61.9% of patients; p high-risk plaque (0, 36.0, and 85.7% of patients; p high risk hsTnI group. Severity of stenosis and presence of vunerable plaque as detected by DSCTA are associated with increasing levels of hsTn I. DSCTA at the time of presentation with the assessment for both stenosis and high-risk plaque improved the diagnostic accuracy for ACS in the intermediate hsTn I group patients.

  10. Coronary Computed Tomography Angiography Versus Radionuclide Myocardial Perfusion Imaging in Patients With Chest Pain Admitted to Telemetry: A Randomized Trial.

    Science.gov (United States)

    Levsky, Jeffrey M; Spevack, Daniel M; Travin, Mark I; Menegus, Mark A; Huang, Paul W; Clark, Elana T; Kim, Choo-Won; Hirschhorn, Esther; Freeman, Katherine D; Tobin, Jonathan N; Haramati, Linda B

    2015-08-04

    The role of coronary computed tomography angiography (CCTA) in the management of symptomatic patients suspected of having coronary artery disease is expanding. However, prospective intermediate-term outcomes are lacking. To compare CCTA with conventional noninvasive testing. Randomized, controlled comparative effectiveness trial. (ClinicalTrials.gov: NCT00705458). Telemetry-monitored wards of an inner-city medical center. 400 patients with acute chest pain (mean age, 57 years); 63% women; 54% Hispanic and 37% African-American; and low socioeconomic status. CCTA or radionuclide stress myocardial perfusion imaging (MPI). The primary outcome was cardiac catheterization not leading to revascularization within 1 year. Secondary outcomes included length of stay, resource utilization, and patient experience. Safety outcomes included death, major cardiovascular events, and radiation exposure. Thirty (15%) patients who had CCTA and 32 (16%) who had MPI underwent cardiac catheterization within 1 year. Fifteen (7.5%) and 20 (10%) of these patients, respectively, did not undergo revascularization (difference, -2.5 percentage points [95% CI, -8.6 to 3.5 percentage points]; hazard ratio, 0.77 [CI, 0.40 to 1.49]; P = 0.44). Median length of stay was 28.9 hours for the CCTA group and 30.4 hours for the MPI group (P = 0.057). Median follow-up was 40.4 months. For the CCTA and MPI groups, the incidence of death (0.5% versus 3%; P = 0.12), nonfatal cardiovascular events (4.5% versus 4.5%), rehospitalization (43% versus 49%), emergency department visit (63% versus 58%), and outpatient cardiology visit (23% versus 21%) did not differ. Long-term, all-cause radiation exposure was lower for the CCTA group (24 versus 29 mSv; P < 0.001). More patients in the CCTA group graded their experience favorably (P = 0.001) and would undergo the examination again (P = 0.003). This was a single-site study, and the primary outcome depended on clinical management decisions. The CCTA and MPI groups did

  11. 29. Triple rule out versus standard coronary computed tomography angiography in evaluation of acute chest pain syndrome.

    Directory of Open Access Journals (Sweden)

    O. smettei

    2016-07-01

    Full Text Available Acute chest pain (ACP in emergency department represents a health care challenge. Triple-rule-out (TRO Computed Tomography Angiography (CTA can provide an evaluation of the coronary arteries, aorta,Pulmonary arteries, and chest structures in one scan. The aim of our work was to evaluate the diagnostic yield of TRO versus cardiac CTA in patients with ACP, In addition to compare the image quality, contrast material and radiation doses of TRO with standard CTA.We hypothesized that TRO CTA has a comparable diagnostic yield to standard coronary CTA, in addition to its ability to add extra diagnostic information. Prospective analysis of 134 TRO CTA data, to assess the presence of coronary artery disease(CAD, Aortic dissection, pulmonary embolism and other chest pathology. Then retrospectively to compare the results with 132 standard CTA. Normal coronaries or non-significant CAD was seen in 97 (72.9% patients, 19 (14.2% had moderate or significant CAD, two (1.5% had aortic dissection, three (2.2% had a pulmonary embolism, 61% had other findings. The image quality score and noise were comparable between the standard and TRO CTA (2.8 ± 0.6 vs 2.96 ± 0.6, P = 0.28 and (30.5 ± 10.6 vs 28.4 ± 1, P = 0.1 respectively. The effective radiation dose was significantly lower in the standard compared to the TRO CTA using prospective (4.4 ± 1.7 vs. 5.1 ± 0.5 mSv = 0.008 and (11.9 vs. 18.3 ± 5 msv, P = 0.0001 for retrospective gating protocols. The contrast dose was lower with standard protocol (83 ± 5 vs 102 ± 9 ml. p = 0.001. TRO CTA is a valid tool for diagnosis of CAD and can provide accurate detection of non-coronary pathology, but it was associated with higher radiation and contrast doses compared to the standard CTA.

  12. Evaluation of optical coherence tomography in the diagnosis of age related macula degeneration compared with fluorescence angiography

    Directory of Open Access Journals (Sweden)

    Fröschl, Barbara

    2007-02-01

    Full Text Available Background: In industrialised nations age-related macular degeneration (AMD is the most common cause of blindness and severe visual impairment. AMD is a disease of the retina characterized by the accumulation of metabolic products in the macula. In early stages drusen and pigment disorders occur, in late stages a dry form is distinguished from the exsudative form with choroidal neovascularisation. AMD causes vision disorders such as blurred vision of the central part of the visual field, leading finally to a dark spot. Several therapies are available for the exsudative form, however an exact diagnosis is partially essential. The gold standard for the diagnosis of AMD is fluorescein angiography (FA, an invasive investigation with intravenous application of a dye. Optical coherence tomography (OCT is a more recent non-invasive procedure. Objectives: The aim of this HTA report is to investigate the efficacy and efficiency of OCT compared to FA. Ethical, societal and legal aspects are also considered. Methods: A systematic literature search was performed in 34 international databases which yielded 2324 articles. Eight publications were included for assessment, according to predefined selection criteria. Results: The number of studies investigating OCT compared to FA in patients with AMD is presently very limited and the quality of the studies is generally low. The number of investigated patients is below 35 in four publications and in only one publication it is above 100. Moreover in most of the articles very selected patient groups are studied. Economic studies concerning the efficiency of OCT compared to FA cannot be identified. DiscussionEven though the patient groups investigated and the objectives of the studies are very heterogenous, all publications uniformly show that OCT cannot replace FA. However, OCT yields additional diagnostic findings and may verify unclear findings of FA. Therefore the application of OCT in addition to FA is useful in

  13. Individual patient data meta-analysis for the clinical assessment of coronary computed tomography angiography: protocol of the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT).

    Science.gov (United States)

    Schuetz, Georg M; Schlattmann, Peter; Achenbach, Stephan; Budoff, Matthew; Garcia, Mario J; Roehle, Robert; Pontone, Gianluca; Meijboom, Willem Bob; Andreini, Daniele; Alkadhi, Hatem; Honoris, Lily; Bettencourt, Nuno; Hausleiter, Jörg; Leschka, Sebastian; Gerber, Bernhard L; Meijs, Matthijs Fl; Shabestari, Abbas Arjmand; Sato, Akira; Zimmermann, Elke; Schoepf, Uwe J; Diederichsen, Axel; Halon, David A; Mendoza-Rodriguez, Vladimir; Hamdan, Ashraf; Nørgaard, Bjarne L; Brodoefel, Harald; Ovrehus, Kristian A; Jenkins, Shona Mm; Halvorsen, Bjørn A; Rixe, Johannes; Sheikh, Mehraj; Langer, Christoph; Martuscelli, Eugenio; Romagnoli, Andrea; Scholte, Arthur Jha; Marcus, Roy P; Ulimoen, Geir R; Nieman, Koen; Mickley, Hans; Nikolaou, Konstantin; Tardif, Jean-Claude; Johnson, Thorsten Rc; Muraglia, Simone; Chow, Benjamin Jw; Maintz, David; Laule, Michael; Dewey, Marc

    2013-02-15

    Coronary computed tomography angiography has become the foremost noninvasive imaging modality of the coronary arteries and is used as an alternative to the reference standard, conventional coronary angiography, for direct visualization and detection of coronary artery stenoses in patients with suspected coronary artery disease. Nevertheless, there is considerable debate regarding the optimal target population to maximize clinical performance and patient benefit. The most obvious indication for noninvasive coronary computed tomography angiography in patients with suspected coronary artery disease would be to reliably exclude significant stenosis and, thus, avoid unnecessary invasive conventional coronary angiography. To do this, a test should have, at clinically appropriate pretest likelihoods, minimal false-negative outcomes resulting in a high negative predictive value. However, little is known about the influence of patient characteristics on the clinical predictive values of coronary computed tomography angiography. Previous regular systematic reviews and meta-analyses had to rely on limited summary patient cohort data offered by primary studies. Performing an individual patient data meta-analysis will enable a much more detailed and powerful analysis and thus increase representativeness and generalizability of the results. The individual patient data meta-analysis is registered with the PROSPERO database (CoMe-CCT, CRD42012002780). The analysis will include individual patient data from published and unpublished prospective diagnostic accuracy studies comparing coronary computed tomography angiography with conventional coronary angiography. These studies will be identified performing a systematic search in several electronic databases. Corresponding authors will be contacted and asked to provide obligatory and additional data. Risk factors, previous test results and symptoms of individual patients will be used to estimate the pretest likelihood of coronary

  14. Individual patient data meta-analysis for the clinical assessment of coronary computed tomography angiography: protocol of the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT

    Directory of Open Access Journals (Sweden)

    Schuetz Georg M

    2013-02-01

    Full Text Available Abstract Background Coronary computed tomography angiography has become the foremost noninvasive imaging modality of the coronary arteries and is used as an alternative to the reference standard, conventional coronary angiography, for direct visualization and detection of coronary artery stenoses in patients with suspected coronary artery disease. Nevertheless, there is considerable debate regarding the optimal target population to maximize clinical performance and patient benefit. The most obvious indication for noninvasive coronary computed tomography angiography in patients with suspected coronary artery disease would be to reliably exclude significant stenosis and, thus, avoid unnecessary invasive conventional coronary angiography. To do this, a test should have, at clinically appropriate pretest likelihoods, minimal false-negative outcomes resulting in a high negative predictive value. However, little is known about the influence of patient characteristics on the clinical predictive values of coronary computed tomography angiography. Previous regular systematic reviews and meta-analyses had to rely on limited summary patient cohort data offered by primary studies. Performing an individual patient data meta-analysis will enable a much more detailed and powerful analysis and thus increase representativeness and generalizability of the results. The individual patient data meta-analysis is registered with the PROSPERO database (CoMe-CCT, CRD42012002780. Methods/Design The analysis will include individual patient data from published and unpublished prospective diagnostic accuracy studies comparing coronary computed tomography angiography with conventional coronary angiography. These studies will be identified performing a systematic search in several electronic databases. Corresponding authors will be contacted and asked to provide obligatory and additional data. Risk factors, previous test results and symptoms of individual patients will be

  15. Preoperative Computerized Tomography and Magnetic Resonance Imaging of the Pancreas Predicts Pancreatic Mass and Functional Outcomes After Total Pancreatectomy and Islet Autotransplant.

    Science.gov (United States)

    Young, Michael C; Theis, Jake R; Hodges, James S; Dunn, Ty B; Pruett, Timothy L; Chinnakotla, Srinath; Walker, Sidney P; Freeman, Martin L; Trikudanathan, Guru; Arain, Mustafa; Robertson, Paul R; Wilhelm, Joshua J; Schwarzenberg, Sarah J; Bland, Barbara; Beilman, Gregory J; Bellin, Melena D

    2016-08-01

    Approximately two thirds of patients will remain on insulin therapy after total pancreatectomy with islet autotransplant (TPIAT) for chronic pancreatitis. We investigated the relationship between measured pancreas volume on computerized tomography or magnetic resonance imaging and features of chronic pancreatitis on imaging, with subsequent islet isolation and diabetes outcomes. Computerized tomography or magnetic resonance imaging was reviewed for pancreas volume (Vitrea software) and presence or absence of calcifications, atrophy, and dilated pancreatic duct in 97 patients undergoing TPIAT. Relationship between these features and (1) islet mass isolated and (2) diabetes status at 1-year post-TPIAT were evaluated. Pancreas volume correlated with islet mass measured as total islet equivalents (r = 0.50, P < 0.0001). Mean islet equivalents were reduced by more than half if any one of calcifications, atrophy, or ductal dilatation were observed. Pancreatic calcifications increased the odds of insulin dependence 4.0 fold (1.1, 15). Collectively, the pancreas volume and 3 imaging features strongly associated with 1-year insulin use (P = 0.07), islet graft failure (P = 0.003), hemoglobin A1c (P = 0.0004), fasting glucose (P = 0.027), and fasting C-peptide level (P = 0.008). Measures of pancreatic parenchymal destruction on imaging, including smaller pancreas volume and calcifications, associate strongly with impaired islet mass and 1-year diabetes outcomes.

  16. Computerized tomography-guided sphenopalatine ganglion pulsed radiofrequency treatment in 16 patients with refractory cluster headaches: Twelve- to 30-month follow-up evaluations.

    Science.gov (United States)

    Fang, Luo; Jingjing, Lu; Ying, Shen; Lan, Meng; Tao, Wang; Nan, Ji

    2016-02-01

    Sphenopalatine ganglion percutaneous radiofrequency thermocoagulation treatment can improve the symptoms of cluster headaches to some extent. However, as an ablation treatment, radiofrequency thermocoagulation treatment also has side effects. To preliminarily evaluate the efficacy and safety of a non-ablative computerized tomography-guided pulsed radiofrequency treatment of sphenopalatine ganglion in patients with refractory cluster headaches. We included and analysed 16 consecutive cluster headache patients who failed to respond to conservative therapy from the Pain Management Center at the Beijing Tiantan Hospital between April 2012 and September 2013 treated with pulsed radiofrequency treatment of sphenopalatine ganglion. Eleven of 13 episodic cluster headaches patients and one of three chronic cluster headaches patient were completely relieved of the headache within an average of 6.3 ± 6.0 days following the treatment. Two episodic cluster headache patients and two chronic cluster headache patients showed no pain relief following the treatment. The mean follow-up time was 17.0 ± 5.5 months. All patients enrolled in this study showed no treatment-related side effects or complications. Our data show that patients with refractory episodic cluster headaches were quickly, effectively and safely relieved from the cluster period after computerized tomography-guided pulsed radiofrequency treatment of sphenopalatine ganglion, suggesting that it may be a therapeutic option if conservative treatments fail. © International Headache Society 2015.

  17. Catheter Angiography

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    Full Text Available ... What are the limitations of Catheter Angiography? What is Catheter Angiography? Angiography is a minimally invasive medical ... them appear bright white. top of page How is the procedure performed? This examination is usually done ...

  18. Catheter Angiography

    Medline Plus

    Full Text Available ... risks? What are the limitations of Catheter Angiography? What is Catheter Angiography? Angiography is a minimally invasive ... of ionizing radiation ( x-rays ). top of page What are some common uses of the procedure? Catheter ...

  19. [High-sensitivity troponin T testing and coronary computed tomography angiography for rapid diagnosis of chest pain in the emergency department].

    Science.gov (United States)

    Durán-Cambra, Albert; Rosselló, Xavier; Sans-Roselló, Jordi; Vila, Montserrat; Hidalgo, Alberto; Rodríguez, Iván Díaz-; Leta, Rubén; Pons-Lladó, Guillem; Ordóñez-Llanos, Jordi; Sionis, Alessandro

    2016-02-01

    To determine the probability of finding significant coronary lesions, the time to diagnosis, and the safety of a new diagnostic approach based on high-sensitivity cardiac troponin T (hsTnT) testing followed by coronary computed tomography angiography (CCTA) in patients with chest pain of possible coronary origin. The method was compared with our hospital emergency department's standard practice. Unblinded randomized controlled trial in a tertiary level university hospital between February 2011 and April 2013. We included emergency patients with chest pain and nondiagnostic electrocardiographic findings. Patients were assigned randomly to the new approach (hsTnT assay, followed by CCTA if the assay findings were negative) or the conventional approach (fourth generation TnT assay and, if negative, followed by an exercise stress test). Invasive coronary angiography was ordered in all patients if the results of either troponin assay, the CCTA, or the stress test were positive. We recorded the results of angiography, time until diagnosis, and all-cause mortality, new myocardial infarction, new unstable angina, or need for revascularization within the next 3 months. Of 102 patients randomized, 7 were excluded; 50 of the remaining 95 patients were assigned to the new strategy, and 45 to the conventional approach. Coronary angiography demonstrated significant lesions in 92.9% of the patients treated with the new strategy and 66.7% of those diagnosed conventionally. A higher percentage of patients were diagnosed within 6 hours with the new approach (20.0% vs 4.4% of conventional-approach patients, P = .023). During the 3 months following diagnosis, 1 death occurred in the intervention group and none in the conventional-approach group. The new strategy could accelerate diagnosis and increase the probability of finding significant coronary lesions, but we found no significant differences in adverse events in the 3 months following diagnosis. These findings should be confirmed

  20. Exploration of peripapillary vessel density in highly myopic eyes with peripapillary intrachoroidal cavitation and its relationship with ocular parameters using optical coherence tomography angiography.

    Science.gov (United States)

    Chen, Qiuying; He, Jiangnan; Hua, Yihong; Fan, Ying

    2017-12-01

    Identifying changes of peripapillary vessel density in highly myopic eyes with peripapillary intrachoroidal cavitation by optical coherence tomography angiography. To investigate peripapillary vessel density and its relationship with other ocular parameters in highly myopic eyes with peripapillary intrachoroidal cavitation. Hospital-based, cross-sectional study. Thirty-five highly myopic eyes with peripapillary intrachoroidal cavitation, 46 highly myopic eyes without peripapillary intrachoroidal cavitation and 36 normal eyes were included in this study. All participants underwent optical coherence tomography angiography to image the retinal vasculature in the peripapillary areas, including the radial peripapillary capillaries and optic nerve head layer. Correlations between vessel density and ocular metrics were analysed. Peripapillary vessel density. In highly myopic eyes, vessel density was significantly lower in eyes with peripapillary intrachoroidal cavitation than in those without in peripapillary (P = 0.014, P = 0.037), inferotemporal (P cavitation (P = 0.012) and myopic maculopathy (P cavitation had lower peripapillary vessel densities, especially in the temporal area, than those without. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

  1. Computerized tomography dose index weighted comparison between two groups of computer tomography equipment; Comparacao do indice de dose em tomografia computadorizada - ponderado (CTDI{sub W}) entre dois grupos de equipamentos de tomografia

    Energy Technology Data Exchange (ETDEWEB)

    Capeleti, Felipe F., E-mail: fcapeleti@gmail.co [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil); Nersissian, Denise Y.; Furquim, Tania A.C. [Universidade de Sao Paulo (IEE/USP), SP (Brazil). Inst. de Eletrotecnica e Energia

    2010-07-01

    This work intended to compare the results of the Computerized Tomography Dose Index (CTDI) between the head and abdomen protocols for different equipment configurations: the first group was composed by equipment with 10 up to 16 slices, the second group presented 40 up to 320 slices detectors. The results has shown variation higher than 20 % for both protocols of the group 1 and variation of 14.5 % and 7.3 %, in group 2, for head and abdomen protocols, respectively. Although having different slices configurations, the other comparison between both groups has shown similar dose impartation to the patients, considering the associated uncertainties with this measurement. (author)

  2. Regional cerebral blood flow during rest and skilled hand movements by xenon-133 inhalation and emission computerized tomography

    DEFF Research Database (Denmark)

    Lauritzen, M; Henriksen, L; Lassen, N A

    1981-01-01

    Regional cerebral blood flow (CBF) was studied in 16 normal adult volunteers during rest and in 10 the study was repeated during skilled hand movements. A fast-rotating ("dynamic"), single-photon emission computerized tomograph (ECT) with four detector heads was used. Xenon-133 was inhaled over a 1...

  3. Comparison of computed tomography pulmonary angiography and point-of-care tests for pulmonary thromboembolism diagnosis in dogs.

    Science.gov (United States)

    Goggs, R; Chan, D L; Benigni, L; Hirst, C; Kellett-Gregory, L; Fuentes, V L

    2014-04-01

    To evaluate the feasibility of CT pulmonary angiography for identification of naturally occurring pulmonary thromboembolism in dogs using predefined diagnostic criteria and to assess the ability of echocardiography, cardiac troponins, D-dimers and kaolin-activated thromboelastography to predict the presence of pulmonary thromboembolism in dogs. Twelve dogs with immune-mediated haemolytic anaemia and evidence of respiratory distress were prospectively evaluated. Dogs were sedated immediately before CT pulmonary angiography using intravenous butorphanol. Spiral CT pulmonary angiography was performed with a 16 detector-row CT scanner using a pressure injector to infuse contrast media through peripheral intravenous catheters. Pulmonary thromboembolism was diagnosed using predefined criteria. Contemporaneous tests included echocardiography, arterial blood gas analysis, kaolin-activated thromboelastography, D-dimers and cardiac troponins. Based on predefined criteria, four dogs were classified as pulmonary thromboembolism positive, three dogs were suspected to have pulmonary thromboembolism and the remaining five dogs had negative scans. The four dogs identified with pulmonary thromboembolism all had discrete filling defects in main or lobar pulmonary arteries. None of the contemporaneous tests was discriminant for pulmonary thromboembolism diagnosis, although the small sample size was limiting. CT pulmonary angiography can be successfully performed in dogs under sedation, even in at-risk patients with respiratory distress and can both confirm and rule out pulmonary thromboembolism in dogs. © 2014 British Small Animal Veterinary Association.

  4. 40. Optical coherence tomography correlates of complex lesions evaluated by coronary angiography in patients with acute coronary syndromes

    Directory of Open Access Journals (Sweden)

    Hesham Refaat

    2015-10-01

    Conclusion: In conclusion, OCT demonstrates PR and thrombosis in the majority of ACS patients presenting with CL. Of note, one third of NCL has PR and thrombosis by OCT. In STEMI, coronary angiography is of limited utility in identifying PR by means of CL and should be implemented with OCT to tailor future therapies.

  5. 307 Is Catheter Diagnostic Cerebral Angiography Still Essential for Patients With Spontaneous Perimesencephalic Subarachnoid Hemorrhage and Negative Computed Tomography Angiogram?

    Science.gov (United States)

    Galal, Ahmed; ElSerry, Tarek H; Aziz, Mohamed Mostafa

    2016-08-01

    Computed tomography (CT) angiography is currently used as the initial diagnostic tool in patients with spontaneous subarachnoid hemorrhage. Eighty-five percent of spontaneous subarachnoid hemorrhages are reported in the literature as caused by a ruptured aneurysm, whereas 10% are termed nonaneurysmal perimesencephalic subarachnoid hemorrhage and carry and excellent prognosis. This retrospective study was conducted to better clarify the diagnostic yield of transfemoral catheter cerebral angiography in light of the current high-quality CT angiogram imaging reported as negative in cases presenting with perimesencephalic subarachnoid hemorrhage. Patients with an admission diagnosis of perimesencephalic subarachnoid hemorrhage and a CT angiogram report as being negative from January 2013 to December 2015 were retrospectively reviewed. CT angiogram findings were correlated with that of the catheter-based diagnostic cerebral angiogram that was done at the time of presentation. Clinical data recorded included age, sex, medical history, and clinical presentation. The authors retrospectively reviewed CT brain, CT angiogram, and digital subtraction angiography images as well as formal reports. A total of 43 patients fulfilled the aforementioned diagnostic criteria of spontaneous perimesencephalic subarachnoid hemorrhage. There were 31 females and 12 males. Ages ranged from 23 to 69 years. All patients had Hunt and Hess grades I or II. There was a false-negative CT angiogram in 4 cases (9.3%) where an underlying aneurysm was identified on digital subtraction angiography, the site of which correlated with the pattern of bleeding. The mean aneurysm size was 2 mm. No complications were related to the catheter angiogram procedure. This study shows that CT angiography, even when read as "negative" for cases assumed to have a benign perimesencephalic pattern of subarachnoid hemorrhage, is still insufficient to exclude underlying pathology as the source of hemorrhage. This study

  6. Non-invasive Heart Team assessment of multivessel coronary disease with coronary computed tomography angiography based on SYNTAX score II treatment recommendations: design and rationale of the randomised SYNTAX III Revolution trial

    NARCIS (Netherlands)

    Cavalcante, Rafael; Onuma, Yoshinobu; Sotomi, Yohei; Collet, Carlos; Thomsen, Brian; Rogers, Campbell; Zeng, Yaping; Tenekecioglu, Erhan; Asano, Taku; Miyasaki, Yosuke; Abdelghani, Mohammad; Morel, Marie-Angèle; Serruys, Patrick W.

    2017-01-01

    The aim of this study was to investigate whether a Heart Team decision-making process regarding the choice of revascularisation strategy based on non-invasive coronary multislice computed tomography angiography (MSCT) assessment of coronary artery disease (CAD) is equivalent to the standard-of-care

  7. CT angiography - abdomen and pelvis

    Science.gov (United States)

    Computed tomography angiography - abdomen and pelvis; CTA - abdomen and pelvis; Renal artery - CTA; Aortic - CTA; Mesenteric CTA ... of the blood vessels inside your belly or pelvis. This test may be used to look for: ...

  8. High-resolution nuclear magnetic resonance imaging and single photon emission computerized tomography--cerebral blood flow in a case of pure sensory stroke and mild dementia owing to subcortical arteriosclerotic encephalopathy (Binswanger's disease)

    DEFF Research Database (Denmark)

    De Chiara, S; Lassen, N A; Andersen, A R

    1987-01-01

    involving visiospatial apraxia; this pointed to decreased function of the right parietal cortex, which was structurally intact on CT and NMRI. Single photon emission computerized tomography by Xenon-133 injection and by hexamethyl-propyleneamine-oxim labeled with Technetium-99m showed asymmetric...

  9. Use of ECG-gated computed tomography, echocardiography and selective angiography in five dogs with pulmonic stenosis and one dog with pulmonic stenosis and aberrant coronary arteries.

    Science.gov (United States)

    Laborda-Vidal, P; Pedro, B; Baker, M; Gelzer, A R; Dukes-McEwan, J; Maddox, T W

    2016-12-01

    Pulmonic stenosis (PS) is the most common congenital cardiac disease in dogs. Boxers and English bulldogs are among the most commonly affected breeds and also commonly associated with an aberrant coronary artery (CA). If an aberrant CA is suspected and balloon valvuloplasty indicated, an intra-operative angiography is recommended prior to the procedure. ECG-gated computed tomography (CT) can be used to screen for CA anomalies in a quick and minimally-invasive way (preventing side effects associated with selective catheter angiography) and allowing early planning of the procedure. The aim of this case series was to report CT findings associated with PS diagnosed by echocardiography. Our database was retrospectively searched for cases of dogs with PS diagnosed by echocardiography, where an ECG-gated CT was performed. A total of six cases were retrieved: all were diagnosed with severe PS. Four dogs had concurrent congenital defects: two dogs had a patent ductus arteriosus, one dog had a ventricular septal defect and an overriding aorta, one dog had an aberrant CA. Detailed CT findings of all cases were reported, including one case of a patent ductus arteriosus and an overriding aorta not identified by transthoracic echocardiography. In addition, an abnormal single left coronary ostium, with a pre-pulmonic right CA was described. In conclusion, despite echocardiography remaining the gold standard for diagnosis and assessment of PS, ECG-gated-CT angiography is a complementary diagnostic method that may provide additional relevant information, shorten surgery/anaesthesia time and reduce the amount of radiation to which the clinician is subjected. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Prevalence of incidental pulmonary findings and early follow-up results in patients undergoing dual-source 64-slice computed tomography coronary angiography.

    Science.gov (United States)

    Yorgun, Hikmet; Kaya, Ergün Barş; Hazirolan, Tuncay; Ateş, Ahmet Hakan; Canpolat, Uğur; Sunman, Hamza; Aytemr, Kudret; Kabakçi, Giray; Tokgözoğlu, Lale; Karçaaltincaba, Muşturay; Akata, Deniz; Oto, Ali

    2010-01-01

    In this study, we aimed to evaluate the incidence of pulmonary abnormalities and document early follow-up results in subjects undergoing multislice computed tomography coronary angiography for the assessment of coronary artery disease. In this retrospective analysis, 1206 patients including 701 men (58.1%) with a mean age of 58.75 (SD, 11.4) years were involved in the study who underwent coronary multislice computed tomography imaging with a 64-slice dual-source scanner. Pulmonary abnormalities were reported as nodules, pulmonary mass, emphysema, bullae, atelectasia, bronchiectasia, pleural effusion, pulmonary fibrosis, and other findings. In total, 186 pulmonary abnormalities were detected in 171 patients (14.1%). Of those, 90 (48.4%) were pulmonary nodules, and 30 (16.1%) were emphysema. Also, we report 3 cases of lung cancer, and 1 case of breast cancer. Early follow-up results revealed stable pulmonary findings. Multislice computed tomography can give important clues including diseases regarding the pulmonary system. It is essential for the reporting practitioner to review the entire scan for pulmonary pathological findings.

  11. Epiploic appendicitis and omental infarction. Findings in the ultrasonography and computerized tomography; Apendicitis epiploica e infarto omental. Hallazgos en ecografia y tomografia computarizada

    Energy Technology Data Exchange (ETDEWEB)

    Migule, A.; Ripolles, T.; Martinez, M. J.; Morote, V.; Ruiz, A. [Hospital Universitario Dr. Peset. Valencia (Spain)

    2001-07-01

    Describe the findings in the ultrasonography and computerized tomography (CT) of the omental infarction and epiploic appendicitis. The clinical and radiological findings of the patients diagnosed in our hospital with epiploic appendicitis or omental infarctions between August 1994 and March 2001 were assessed retrospectively. We found a high incidence (42 cases) of these two diseases: 30 patients with diagnosis of epiploic appendicitis and 12 with the diagnosis of omental infarction. Four patients were treated surgically, while the remaining 38 were conservatively, without posterior complications. The ultrasonography and CT images is characteristics. making it possible to make a diagnosis of epiploic appendicitis or omental infarction with certainty. It is not necessary to make a differential diagnosis between the two entities because their prognosis and treatment are similar. Their incidence is much more frequent than that previously published. (Author) 19 refs.

  12. Sensitivity and specificity of optical coherence tomography angiography (OCT-A) for detection of choroidal neovascularization in real-life practice and varying retinal expertise level.

    Science.gov (United States)

    Souedan, Vaël; Souied, Eric H; Caillaux, Violaine; Miere, Alexandra; Ameen, Ala El; Blanco-Garavito, Rocio

    2017-05-25

    To evaluate the diagnostic accuracy of OCT angiography (OCT-A) detecting or predicting choroidal neovascularization (CNV), by ophthalmologists of disparate degrees of skills in retinal diseases, using spectral domain optical coherence tomography (SD-OCT) and fluorescein angiography (FA) as a standard reference. Retrospective observational case series. Patient presenting maculopathy and complete imaging were included. FA, SD-OCT, OCT-A and FA coupled to SD-OCT images were graded independently for presence or absence of CNV by ophthalmologists with varying expertise levels. Overall sensitivity of OCT-A was 85.62% (95% CI 79.04-90.76%) and specificity was 81.51% (95% CI 73.36-88.03). Sensitivity of FA was 74.51% (95% CI 66.84-81.20), and specificity was 82.35% (95% CI 74.30-88.73). Sensitivity of FA + SD-OCT was 92.72% (95% CI 87.34-96.30), and specificity was 90.91% (95% CI 84.31-95.37). OCT-A has good sensitivity and specificity for the detection of CNV in all expertise level groups. OCT-A may soon become a routine tool for CNV diagnosis and follow-up.

  13. Visualization of microaneurysms using optical coherence tomography angiography: comparison of OCTA en face, OCT B-scan, OCT en face, FA, and IA images.

    Science.gov (United States)

    Hamada, Masafumi; Ohkoshi, Kishiko; Inagaki, Keiji; Ebihara, Nobuyuki; Murakami, Akira

    2018-01-30

    To compare the visualization of microaneurysms (MAs) in patients with diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA) with that using fluorescein angiography (FA). Prospective, clinical, and experimental. This study was a prospective evaluation of imaging technology. Thirty-seven eyes of 33 patients with DR were scanned using an OCTA instrument. The 83 MAs that were confirmed on OCT B-scan and OCT en face images were evaluated using OCTA, and these findings were compared with those evaluated using FA. Of the 83 MAs confirmed on OCT B-scan images, 73 (88%) were clearly visualized on the OCTA en face images as nodular or comma-shaped structures, while the remaining 12% did not present with a typical MA or vascular structure on the OCTA en face images at the relevant positions. Seventy-four of the 83 MAs (87%) confirmed on the OCT B-scan images presented as punctate hyperfluorescent spots on the FA images. On the FA images, 8 of 9 (88%) MAs absent on the OCTA en face images presented as hyperfluorescent spots. Visualization of the MAs on the OCTA en face images did not correlate with the OCT B-scan images of the MA lumens (open, closed, or heterogeneous). For diabetic maculopathy, OCTA en face images do not present with comprehensive MAs images, indicating that some MAs might be overlooked with OCTA en face images.

  14. Comparison of the diagnostic performance of 64-slice computed tomography coronary angiography in diabetic and non-diabetic patients with suspected coronary artery disease

    Directory of Open Access Journals (Sweden)

    Annoni Andrea

    2010-11-01

    Full Text Available Abstract Background Diabetics have high prevalence of subclinical coronary artery disease (CAD with typical characteristics (diffuse disease, large calcifications. Although 64-slice multidetector computed tomography (MDCT coronary angiography has high diagnostic accuracy to detect CAD, its diagnostic performance in diabetics with suspected CAD is unknown. To compare the diagnostic performance of 64-slice MDCT between diabetics and non-diabetics with suspected CAD scheduled for invasive coronary angiography (ICA. Methods We enrolled one hundred and five diabetic patients (92 men, age 65 +/- 9 years, Group 1 and 105 non-diabetic patients (63 men, age 63+/-5 years, Group 2 with indication to ICA for suspected CAD undergoing coronary 64-slice MDCT before ICA. Results In Group 1, the overall feasibility of coronary artery visualization was 93.8%. The most frequent artifact was blooming due to large coronary calcifications (54 artifacts, 67%. In Group 2, the overall feasibility was significantly higher vs. Group 1 (97%, p Conclusions Although MDCT has high sensitivity for early identification of significant CAD in diabetics, its diagnostic performance is significantly reduced in these patients as compared to non-diabetics with similar clinical characteristics.

  15. Transluminal attenuation gradient in coronary computed tomography angiography for determining stenosis severity of calcified coronary artery: a primary study with dual-source CT

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Minwen; Wei, Mengqi; Wen, Didi; Zhao, Hongliang; Liu, Ying; Li, Jian [Fourth Military Medical University, Department of Radiology, Xijing Hospital, Xi' an, Shaanxi Province (China); Li, Jiayi [Fourth Military Medical University, Department of Cardiology, Xijing Hospital, Xi' an, Shaanxi Province (China)

    2015-05-01

    To evaluate the diagnostic accuracy of transluminal attenuation gradient (TAG) for stenosis severity of calcified lesions assessed by coronary computed tomography angiography (CCTA). One hundred seven patients who underwent CCTA and coronary angiography (CAG) were enrolled. TAGs of 309 major epicardial coronary arteries were measured. The impact of plaque composition, Agatston scores, and lesion length ratio on TAG were analyzed. Diagnostic performance vs. CAG of TAG, CCTA, and combined TAG/CCTA were evaluated, and incremental value of TAG for reclassification of CCTA stenosis severity in calcified lesions was also analyzed. TAG decreased consistently with stenosis severity. TAG was significantly lower in coronary arteries with calcification scores >300 and lesion length ratios >2/3. TAG improved diagnostic accuracy of CCTA (c-statistic =0.982 vs. 0.942, P = 0.0001) in calcified lesions, and the sensitivity, specificity, positive, and negative predictive values of TAG cutoff ≤ -11.33 were 72 %, 91 %, 88 %, and 78 %, respectively. The addition of TAG to CCTA resulted in significant reclassification (NRI =0.093, P = 0.022) in calcified vessels. Measurement of TAG may improve diagnostic performance and reclassification of CCTA in coronary stenosis caused by calcified lesions. (orig.)

  16. Performance and efficacy of 320-row computed tomography coronary angiography in patients presenting with acute chest pain: results from a clinical registry.

    Science.gov (United States)

    van Velzen, J E; de Graaf, F R; Kroft, L J; de Roos, A; Reiber, J H C; Bax, J J; Jukema, J W; Schuijf, J D; Schalij, M J; van der Wall, E E

    2012-04-01

    The purpose of this study was to evaluate the performance of 320-row computed tomography angiography (CTA) in the identification of significant coronary artery disease (CAD) in patients presenting with acute chest pain and to examine the relation to outcome during follow-up. A total of 106 patients with acute chest pain underwent CTA to evaluate presence of CAD. Each CTA was classified as: normal, non-significant CAD (patients, 23 patients (22%) had a normal CTA, 19 patients (18%) had non-significant CAD on CTA, 59 patients (55%) had significant CAD on CTA, and 5 patients (5%) had non-diagnostic image quality. In total, 16 patients (15%) were immediately discharged after normal CTA and 90 patients (85%) underwent invasive coronary angiography. Sensitivity, specificity, and positive and negative predictive values to detect significant CAD on CTA were 100, 87, 93, and 100%, respectively. During mean follow-up of 13.7 months, no cardiovascular events occurred in patients with a normal CTA examination. In patients with non-significant CAD on CTA, no cardiac death or myocardial infarctions occurred and only 1 patient underwent revascularization due to unstable angina. In patients presenting with acute chest pain, an excellent clinical performance for the non-invasive assessment of significant CAD was demonstrated using CTA. Importantly, normal or non-significant CAD on CTA predicted a low rate of adverse cardiovascular events and favorable outcome during follow-up.

  17. Evaluation of the normal thoracic and abdominal aorta diameters by computerized tomography; Avaliacao dos diametros normais da aorta toracica e abdominal pela tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Lucarelli, Claudio Luiz

    1995-07-01

    The study was undertaken to evaluate, through computerized tomography, the diameters of the normal thoracic and abdominal aorta, as well as they are connected to gender, age and body surface area; and the ratio between measurements obtained at the ascending and descending limbs of the thoracic aorta, and between the abdominal aortic diameters. For that reason, we measured the widest anteroposterior diameters of the thoracic aortas at the levels of the arch, the root, the pulmonary artery, and the thoracic-abdominal transition, as well as the level of the emergence of the superior mesenteric artery, of the renal hila and just cephalad to the bifurcation of the abdominal aortas of 350 patients without cardiovascular diseases who had undergone computerized tomography of the thorax and/or abdomen for any other reasons. Observation and statistic analyses led us to conclude that: 1) both the thoracic and abdominal aortic diameters are reduced from their proximal to their distal portions; 2) the body surface influences the size of the aorta, although only extreme variations alter the vessel's caliber; 3) vessel diameter was observed to gradually increase with age; 4) men were found to have larger diameters than age matched women; 5) the ratio between the ascending and descending aortic diameters varies according to gender and age; 6) the relations between abdominal aortic diameters measured at the level of renal hila and cephalad to the bifurcation are independent from gender and age. But the relation between those measured at the level of the superior mesenteric artery and cephalad to the bifurcation are linked to gender, but not to age. (author)

  18. Multidetector computed tomography angiography in clinically suspected hyperacute ischemic stroke in the anterior circulation: an etiological workup in a cohort of Brazilian patients

    Directory of Open Access Journals (Sweden)

    Felipe Torres Pacheco

    2015-05-01

    Full Text Available Objective The potential of computed tomography angiography (CTA was assessed for early determination of stroke subtypes in a Brazilian cohort of patients with stroke. Method From July 2011 to July 2013, we selected patients with suspected hyperacute stroke (< 6 hours. Intracranial and cervical arteries were scrutinized on CTA and their imaging features were correlated with concurrent subtype of stroke. Results Stroke was documented in 50/106 selected patients (47.2% based on both clinical grounds and imaging follow-up (stroke group, with statistically significant arterial stenosis and vulnerable plaques on CTA. Intracranial large artery disease was demonstrated in 34% of patients in the stroke group. Partial territorial infarct prevailed (86% while artery-to-artery embolization was the most common stroke mechanism (52%. Conclusion Multidetector CTA was useful for the etiologic work-up of hyperacute ischemic stroke and facilitated the knowledge about the topographic pattern of brain infarct in accordance with its causative mechanism.

  19. Epicardial Adipose Tissue Is Associated with Plaque Burden and Composition and Provides Incremental Value for the Prediction of Cardiac Outcome. A Clinical Cardiac Computed Tomography Angiography Study.

    Directory of Open Access Journals (Sweden)

    Gitsios Gitsioudis

    Full Text Available We sought to investigate the association of epicardial adipose tissue (eCAT volume with plaque burden, circulating biomarkers and cardiac outcomes in patients with intermediate risk for coronary artery disease (CAD.177 consecutive outpatients at intermediate risk for CAD and completed biomarker analysis including high-sensitive Troponin T (hs-TnT and hs-CRP underwent 256-slice cardiac computed tomography angiography (CCTA between June 2008 and October 2011. Patients with lumen narrowing ≥50% exhibited significantly higher eCAT volume than patients without any CAD or lumen narrowing 3 risk factors, presence of CAD, hs-CRP and hs-TnT.Epicardial adipose tissue volume is independently associated with plaque burden and maximum luminal narrowing by CCTA and may serve as an independent predictor for cardiac outcomes in patients at intermediate risk for CAD.

  20. Exposure to Cigarette Smoke and the Morphology of Atherosclerotic Plaques in the Extracranial Arteries Assessed by Computed Tomography Angiography in Patients wit