Dynamic Images (dynamic + image)

Distribution by Scientific Domains


Selected Abstracts


Use of time resolved magnetic resonance imaging in the diagnosis of pelvic congestion syndrome

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2010
Tarun Pandey MD
Abstract We describe the efficacy of time-resolved MR angiography in diagnosing a case of pelvic congestion syndrome (PCS). MR angiography, using four-dimensional (4D) TRAK (Time-Resolved Angiography using Keyhole) technique was used in an 81-year-old woman presenting with low backache, pelvic pain, and left pelvic fullness. Dynamic images were obtained in multiple vascular phases including arterial, arteriovenous, and venous phases. The high temporal resolution of 4D TRAK could demonstrate early retrograde left ovarian vein filling as well as multiple dilated pelvic varices, allowing the prospective diagnosis of PCS to be made. Although uncommon in this age group, the diagnosis was subsequently confirmed on conventional catheter venography with symptomatic relief after successful embolization of the incompetent left ovarian vein. The MRA and correlative catheter venography images are presented in this case report. J. Magn. Reson. Imaging 2010;32:700,704. © 2010 Wiley-Liss, Inc. [source]


Tailoring visual images to fit: Value creation in persuasive messages

EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2010
Lucia Mannetti
The present studies aimed to extend Regulatory Fit Theory in the domain of persuasive communication by (a) using printed advertisement images without any verbal claim, instead of purely or mostly verbal messages; (b) selecting the images to fit the distinct orientations of regulatory mode rather than regulatory focus; and (c) priming regulatory mode orientation instead of relying on chronic prevalence of either locomotion or assessment orientation. We found that recipients primed with a locomotion orientation experienced fit, and were more persuaded, when exposed to "dynamic" versus "static" visual images; conversely, recipients primed with an assessment orientation experienced fit and were more persuaded when exposed to "static" versus "dynamic" images. Our findings show that the experience of fit can be induced by visual messages, resulting in positive effects in terms of attitude toward product advertisement and estimated price of advertised products. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Hemodynamic analysis of intracranial aneurysms with moving parent arteries: Basilar tip aneurysms

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 10 2010
Daniel M. Sforza
Abstract The effects of parent artery motion on the hemodynamics of basilar tip saccular aneurysms and its potential effect on aneurysm rupture were studied. The aneurysm and parent artery motions in two patients were determined from cine loops of dynamic angiographies. The oscillatory motion amplitude was quantified by registering the frames. Patient-specific computational fluid dynamics (CFD) models of both aneurysms were constructed from 3D rotational angiography images. Two CFD calculations were performed for each patient, corresponding to static and moving models. The motion estimated from the dynamic images was used to move the surface grid points in the moving model. Visualizations from the simulations were compared for wall shear stress (WSS), velocity profiles, and streamlines. In both patients, a rigid oscillation of the aneurysm and basilar artery in the anterio-posterior direction was observed and measured. The distribution of WSS was nearly identical between the models of each patient, as well as major intra-aneurysmal flow structures, inflow jets, and regions of impingement. The motion observed in pulsating intracranial vasculature does not have a major impact on intra-aneurysmal hemodynamic variables. Parent artery motion is unlikely to be a risk factor for increased risk of aneurysmal rupture. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Sonographic examination of the oral phase of swallowing: Bolus image enhancement

JOURNAL OF CLINICAL ULTRASOUND, Issue 2 2002
Michael J. Casas DDS
Abstract Purpose The purpose of this study was to evaluate the ability of 4 liquid boluses to enhance pixel brightness and the ease with which the boluses could be identified during the sonographic evaluation of oral swallowing in healthy young adults. Methods Ten healthy adult volunteers (5 men and 5 women), ranging in age from 21 to 31 years, underwent sonographic evaluation of the oral phase of swallowing while sitting in their usual feeding position. We compared the ability of the 4 following liquids to improve sonographic visualization of swallowing with that of water: a carbonated cola beverage, 5.0 ml of Thick-It in 120 ml of water, 2.5 ml of Thick-It in 120 ml of water, and 7.5 ml of confectioners' sugar in 120 ml of water. Water was used as a control. In each case, 5 ml of the liquid was introduced into the subject's oral cavity using a syringe, and the subject was instructed to swallow. Digitized still images and recorded video sequences of sonographic examinations of the swallowing were analyzed. The brightness of the bolus image on selected digitized video frames was measured digitally using Image Analyst software. Pixel brightness within selected regions of interest for each of the test liquids was statistically compared with that for water. Seven clinicians rated the visualization of each test liquid and water on paired sonographic videotape sequences. These ratings and the level of agreement between them were statistically tested. Results Only the carbonated cola beverage demonstrated statistically greater pixel brightness than that of water on digitized video frames (p = 0.01), whereas both cola (with a moderate inter-rater agreement, , = 0.50) and 5.0 ml Thick-It mixed with 120 ml of water (with a fair inter-rater agreement, , = 0.24) were significantly better visualized on sonographic video sequences. Conclusions The digital still-frame analysis confirmed the clinicians' ratings of bolus visualization on real-time sonography, but dynamic sonography is more important than still frames in assessing sonographic swallow media because the dynamic images more closely parallel what is seen in clinical practice. Future investigations of sonographic contrast agents for use in the examination of the oral phase of swallowing should use both static digital (still-frame) and dynamic (real-time) assessment methods, as well as expert reviewers. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:83,87, 2002; DOI 10.1002/jcu.10034 [source]


Recent advances in breast MRI and MRS

NMR IN BIOMEDICINE, Issue 1 2009
S. Sinha
Abstract Breast MRI is an area of intense research and is fast becoming an important tool for the diagnosis of breast cancer. This review covers recent advances in breast MRI, MRS, and image post-processing and analysis. Several studies have explored a multi-parametric approach to breast imaging that combines analysis of traditional contrast enhancement patterns and lesion architecture with novel methods such as diffusion, perfusion, and spectroscopy to increase the specificity of breast MRI studies. Diffusion-weighted MRI shows some potential for increasing the specificity of breast lesion diagnosis and is even more promise for monitoring early response to therapy. MRS also has great potential for increasing specificity and for therapeutic monitoring. A limited number of studies have evaluated perfusion imaging based on first-pass contrast bolus tracking, and these clearly identify that vascular indices have great potential to increase specificity. The review also covers the relatively new acquisition technique of MR elastography for breast lesion characterization. A brief survey of image processing algorithms tailored for breast MR, including registration of serial dynamic images, segmentation and extraction of morphological features of breast lesions, and contrast uptake modeling, is also included. Recent advances in MRI, MRS, and automated image analysis have increased the utility of breast MR in diagnosis, screening, management, and therapy monitoring of breast cancer. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Diagnosis of vocal cord dysfunction in asthma with high resolution dynamic volume computerized tomography of the larynx

RESPIROLOGY, Issue 8 2009
Peter W. HOLMES
ABSTRACT Background and objective: Vocal cord dysfunction (VCD) often masquerades as asthma and reports have suggested that up to 30% of patients with asthma may have coexistent VCD. Diagnosis of VCD is difficult, in part because it involves laryngoscopy which has practical constraints, and there is need for rapid non-invasive diagnosis. High speed 320-slice volume CT demonstrates laryngeal function during inspiration and expiration and may be useful in suspected VCD. Methods: Endoscopy and high resolution 320-slice dynamic volume CT were used to examine and compare laryngeal anatomy and movement in a case of subglottic stenosis and in a patient with confirmed VCD. Nine asthmatics with ongoing symptoms and suspected VCD also underwent 320-slice dynamic volume CT. Tracheal and laryngeal anatomy and movement were evaluated and luminal areas were measured. Reductions in vocal cord luminal area >40%, lasting for >70% duration of inspiration/expiration, were judged to be consistent with VCD. Results: Studies of subglottic tracheal stenosis validated anatomical similarities between endoscopy and CT images. Endoscopy and 320-slice volume CT also provided comparable dynamic images in a patient with confirmed VCD. A further nine patients with a history of severe asthma and suspected VCD were studied using CT. Four patients had evidence of VCD and the median reduction of luminal area during expiration was 78.2% (range 48.2,92.5%) compared with 10.4% (range 4.7,30%) in the five patients without VCD. Patients with VCD had no distinguishing clinical characteristics. Conclusions: Dynamic volume CT provided explicit images of the larynx, distinguished function of the vocal cords during the respiratory cycle and could identify putative VCD. The technique will potentially provide a simple, non-invasive investigation to identify laryngeal dysfunction, permitting improved management of asthma. [source]