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Sample records for ecg-gated blood pool

  1. Experimental and clinical analyses of optimum Fourier filtering in ECG-gated blood pool scintigraphy

    International Nuclear Information System (INIS)

    Shimabukuro, Kunisada

    1988-01-01

    A phantom study was undertaken to determine the optimum order harmonics in Fourier analysis for volume curves obtained by ECG-gated blood pool scintigraphy. The volume curve obtained by Tc-99m scintigraphy was computed by the 1st through 10th order harmonics of Fourier transform. The shape of each volume curve fitted by Fourier transform was compared with the shape of the generated ideal curve. Curves fitted with the 3rd or more order harmonics were approximate to the ideal curve in shape during the systolic phase. The 6th to 10th order harmonics were suitable for the early diastole phase. As determined by peak ejection rate and peak filling rate (PFR), the 6th order harmonics was superior to the 3rd order harmonics in evaluating early diastolic abnormalities. In the clinical settings, there was no difference between the 3rd and 6th order harmonics in evaluating systolic abnormalities; however, the 6th order harmonics was more sensitive than the 3rd order harmonics in evaluating early diastolic abnormalities. The 6th order harmonics significantly reflected PFR in the group of hypertrophic cardiomyopathy (n=10) and time to PFR in the groups of old myocardial infarction (n=10) and angina pectoris (n=10). In conclusion, the 6th to 9th order harmonics of Fourier analysis may be useful in analyzing both systolic and early diastolic phases inf left ventricular volume curves obtained from ECG-gated cardiac blood pool scintigraphy. (Namekawa, K)

  2. ECG-gated blood pool tomography in the determination of left ventricular volume, ejection fraction, and wall motion

    International Nuclear Information System (INIS)

    Underwood, S.R.; Ell, P.J.; Jarritt, P.H.; Emanuel, R.W.; Swanton, R.H.

    1984-01-01

    ECG-gated blood pool tomography promises to provide a ''gold standard'' for noninvasive measurement of left ventricular volume, ejection fraction, and wall motion. This study compares these measurements with those from planar radionuclide imaging and contrast ventriculography. End diastolic and end systolic blood pool images were acquired tomographically using an IGE400A rotating gamma camera and Star computer, and slices were reconstructed orthogonal to the long axis of the heart. Left ventricular volume was determined by summing the areas of the slices, and wall motion was determined by comparison of end diastolic and end systolic contours. In phantom experiments this provided an accurate measurement of volume (r=0.98). In 32 subjects who were either normal or who had coronary artery disease left ventricular volume (r=0.83) and ejection fraction (r=0.89) correlated well with those using a counts based planar technique. In 16 of 18 subjects who underwent right anterior oblique X-ray contrast ventriculography, tomographic wall motion agreed for anterior, apical, and inferior walls, but abnormal septal motion which was not apparent by contrast ventriculography, was seen in 12 subjects tomographically. All 12 had disease of the left anterior descending coronary artery and might have been expected to have abnormal septal motion. ECG-gated blood pool tomography can thus determine left ventricular volume and ejection fraction accurately, and provides a global description of wall motion in a way that is not possible from any single planar image

  3. New approach for simplified and automated measurement of left ventricular ejection fraction by ECG gated blood pool scintigraphy

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    Inagaki, Suetsugu; Adachi, Haruhiko; Sugihara, Hiroki; Katsume, Hiroshi; Ijichi, Hamao; Okamoto, Kunio; Hosoba, Minoru

    1984-12-01

    Background (BKG) correction is important but debatable in the measurement of Left ventricular ejection fraction (LVEF) with ECG gated blood pool scintigraphy. We devised a new simplified BKG processing (fixed BKG method) without BKG region-of-interest (ROI) assignment, and the accuracy and reproducibility were assessed in 25 patients with various heart diseases and 5 normal subjects by comparison with LVEF obtained by contrast levolgraphy (LVG-EF). Four additional protocols for LVEF measurement with BKG-ROI assignment were also assessed for reference. LVEF calculated using the fixed BKG ratio of 0.64 (BKG count rates were 64%) of end-diastolic count rates of LV) with ''Fixed'' LV-ROI was best correlated with LVG-EF (r = 0.936, p < 0.001) and most approximated (Fixed BKG ratio method EF: 61.1 +- 20.1, LVG-EF: 61.2 +- 20.4% (mean +- SD)) among other protocols. The wide availability of the fixed value of 0.64 was tested in various diseases, body size and end-diastolic volume by LVG, and the results were to be little influenced by them. Furthermore, fixed BKG method produced lower inter-and intra- observer variability than other protocols requiring BKG-ROI assignment, probably due to its simplified processing. In conclusion, fixed BKG ratio method simplifies the measurement of LVEF, and is feasible for automated processing and single probe system.

  4. Evaluation of left ventricular function in patients with atrial fibrillation by ECG gated blood pool scintigraphy. Using frame count normalization method

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    Akanabe, Hiroshi; Oshima, Motoo; Sakuma, Sadayuki

    1988-07-01

    The assumption necessary to perform ECG gated blood pool scintigraphy (EGBPS) are seemingly not valid for patients with atrial fibrillation (af), since they have wide variability in cardiac cycle length. The data were acquired in frame mode within the limits of mean heart rate of fix the first diastolic volume, and were calculated by frame count normalization (FCN) method to correct total counts in each frame. EGBPS were performed twelve patients with af, who were operated against valvular disease. The data acquired within mean heart rate +-10 % in frame mode were divided to 32 frames, and calculated total frame counts. With FCN method total frame counts from at 22nd to 32nd frame were multiplied to be equal to the average of total frame counts. FCN method could correct total frame counts at the latter frames. And there was good correlation between left ventricular ejection fraction calculated from scintigraphy and that from contrast cineangiography. Thus EGBPS with FCN method may be allow estimation of cardiac function even in subjects with af.

  5. Evaluation of left ventricular function in patients with atrial fibrillation by ECG gated blood pool scintigraphy. Analysis of left ventricular filling and function curve

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    Inagaki, Suetsugu; Adachi, Haruhiko; Sugihara, Hiroki

    1985-12-01

    ECG gated blood pool scintigraphy (EGBP) is not always valid for the patients with atrial fibrillation (AF), since they have wide variability in cardiac cycle length (CL). To evaluate the left ventricular (LV) function during AF by EGBP, we devised a new processing algorithm to construct multiple gated images discriminated by preceding R-R interval (PRR) from the data acquired in list mode. 18 patients with AF were studied as to; 1) How affect the PRR on cardiac indices such as EF, TES, PER or TPER, 2) Comparison with conventional method getting all CL data, 3) LV filling curves derived by plotting EDV against PRR, 4) The slope and position of LV function curves (LVFC) derived by plotting SV against EDV. In most cases, EF, PER and TES were increased with longer PRR, and those by conventional method nearly corresponded to the average values obtained by our new method. Impairment of ventricular filling was demonstrated in the cases of mitral stenosis and constrictive pericarditis. LVFC of CHF group was situated at right and downward to controls, and left and upward shift was observed after treatment. The slope of LVFC was reduced in relation to the progression of NYHA's functional class. In conclusion, this new algorithm processing irregular CL enables LV filling and function curves to draw, which are useful in the evaluation of cardiac performance in the subjects with AF.

  6. Evaluation by means of ECG-gated cardiac blood pool scintigraphy of global and regional left ventricular function at rest and during exercise in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Sauer, E.; Sebening, H.; Lutilsky, L.; Dressler, H.; Hoer, G.; Pabst, H.W.; Bloemer, H.; Technische Univ. Muenchen

    1978-01-01

    ECG-gated cardiac blood pool scintigraphy permits a non-invasive determination of the end-diastolic and end-systolic ventricular volumens and of the ejection fraction as well as a qualitative description of regional ventricular wall motion at rest and during exercise. In 6 healthy persons a significant increase of the ejection fraction from 66 +- 7% at rest to 78 +- 3% during exercise (p [de

  7. Assessment of left ventricular function in patients with atrial fibrillation by left ventricular filling and function curves determined by ECG gated blood pool scintigraphy

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    Inagaki, Suetsugu

    1986-06-01

    Accurate cardiac function in patients with atrial fibrillation (Af) is difficult to assess, since a wide fluctuation of cardiac cycle makes the ventricular hemodynamics variable. Although ECG gated blood pool scintigraphy (EGBPS) is useful to evaluate left ventricular (LV) function, a conventional EGBPS might have a problem in applying to Af. Therefore, a new processing algorithm was devised to make multiple gated images discriminated by preceding R-R intervals (PRR), and LV filling and function curves were obtained in 62 patients with Af to evaluate LV function. LV filling curve, obtained by plotting end-diastolic volume (EDV) againt PRR, demonstrated that the blood filling was impaired in mitral stenosis and constrictive pericarditis, but recovered after mitral commissurotomy. LV function curve, by plotting stroke volume (SV) againt EDV, was quantitatively analysed by the indices such as Slope and Position. Both indices reduced significantly in heart failure. When compared among underlying diseases individually, the indices decreased in the following order; lone Af, hyperthyroidism, senile Af, hypertension, mitral valve disease, ischemic heart disease, dilated cardiomyopathy and aortic regurgitation. After the treatment with digitalis and/or diuretics, left and upward shift of function curve was observed. The rise in heart rate by atropine infusion made Slope and Position unchanged, and which implied that function curve was little influenced by heart rate per se. The rise in systolic blood pressure by angiotensin-II infusion caused shifts in function curve to rightward and downward. Downward shift, mostly seen in patients with gentler slope in control state, may imply afterload mismatch due to a decrease in preload reserve. (J.P.N.).

  8. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    International Nuclear Information System (INIS)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun; Lee, Hyong Woo; Chung, Jin Hong

    1990-01-01

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  9. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

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    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun [Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, Hyong Woo; Chung, Jin Hong [Yeongnam National University College of Medicine, Daegu (Korea, Republic of)

    1990-07-15

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  10. Assessment of left ventricular filling in various heart disease, especially in ischemic heart disease, by ECG-gated cardiac blood pool scintigraphy

    International Nuclear Information System (INIS)

    Nakagawa, Hiroaki

    1986-01-01

    Using ECG-gated cardiac blood pool scintigraphy (BPS), left ventricular (LV) diastolic function was evaluated in various heart disease, especially in ischemic heart disease (IHD). LV function indices (2 systolic and 9 diastolic) were obtained from LV time activity curve derived from BPS. Among various diastolic indices, peak filling rate (PFR) and 2 other indices were significantly influenced by heart rate (HR), so corrected values for HR were used for this study. Various degrees of disturbance in diastolic filling were found in many cases without systolic impairment. According to the mechanism responsible for diastolic impairment, LV time activity curve showed a characteristic pattern. In IHD, filling disturbance in early diastole was observed before the impairment of systolic contraction developed, so it was thought to be an early predictor of cardiac failure. In the scar region of myocardial infarction (MI), decrease in regional ejection fraction and asynchrony in wall motion were shown, and these resulted in marked deterioration of early diastolic filling. On the other hand in angina pectoris (AP), such systolic disorders were not shown in the ischemic region perfused by stenotic coronary artery, although the disturbance of regional filling was found. The exercise capacity in AP was more related to the impairment in diastolic function at resting state than in systolic function, and furthermore the reserve of diastolic function as well as of systolic function was shown to be an important determinant of exercise capacity in AP. As HR increased, increase of PFR and decrease in time to peak filling was found, which was thought to be a sort of compensation for the shortening diastolic time due to increase in HR during exercise. Such compensation was decreased in AP with reduced exercise capacity. (J.P.N.)

  11. Clinical evaluation of the Tl-201 ECG-gated myocardial SPECT

    International Nuclear Information System (INIS)

    Mochizuki, Teruhito

    1989-01-01

    In order to evaluate the clinical usefulness of the Tl-201 ECG-gated myocardial single photon emission computed tomography (SPECT), we compared the wall motion and the grade of the Tl-201 uptake of the ECG-gated myocardial SPECT with the wall motion of the ECG-gated blood pool SPECT. Materials were 87 patients of 50 old myocardial infarctions (OMIs), 19 hypertrophic cardiomyopathies (HCMs), 2 dilated cardiomyopathies (DCMs) and 16 others. After intravenous injection of 111-185 MBq (3-5 mCi) of Tl-201 at rest, the projection data were acquired using a rotating gamma-camera through 180deg, from RAO 45deg in 24 directions, each of which consisted of 80-100 beats. For the reconstruction of ED, ES and non-gated images, R-R interval was divided into about 20 (18-22) fractions. In 348 regions of interest (anterior, septal, lateral and inferior wall) in 87 cases, wall motion and the Tl-201 uptake were evaluated to three grades (normal, hypokinesis and akinesis; normal, low and defect, respectively), which were compared with the wall motion of the ECG-gated blood pool SPECT. The wall motion and the grade of the Tl-201 uptake of the ECG-gated myocardial SPECT correlated well with the wall motion of the ECG-gated blood pool SPECT (96.6% and 87.9%, respectively). In conclusion, the ECG-gated myocardial SPECT can provide clear perfusion images and is a very useful diagnostic strategy to evaluate the regional wall motion and perfusion simultaneously. (author)

  12. Clinical usefullness of ECG-triggered single photon emission comuter tomography of blood-pool

    International Nuclear Information System (INIS)

    Eilles, Chr.; Boerner, W.; Strauss, P.; Gerhards, W.; Reiners, Ch.

    1982-01-01

    ECT allows direct measurement of the volume of an organ and imaging without disturbing background-superposition. This makes ECT to an useful instrument for ECG-gated blood-pool imaging. Acquisition is made after the injection of 25 mCi Tc-99m HSA with a rotating Anger-Camera-System. ECG-gated imaging is done for each projection; herewith 50-70 cycles per projection are added according to the phase of the heart-cycle. Transversal-Sections of the heart are reconstructed with filtered-back-projection. For each slice a representative cycle, consisting of 10-16 frames, is computed. As shown by our group before a good quality of the reconstructed images can be obtained. Comparison is made with the results of the ECG-gated blood-pool-ECT, the results of the conventional blood-pool-studies and with the results of Laevo-Cardiography. (Author)

  13. Abnormal intraluminal signal within the pulmonary arteries on MR imaging: Differentiation between slow blood flow and thrombus using an ECG-gated; multiphasic: Spin-echo technique

    International Nuclear Information System (INIS)

    White, R.D.; Higgins, C.B.

    1986-01-01

    The authors evaluated abnormal MR imaging signal patterns in the pulmonary arteries of 22 patients with pulmonary hypertension (n = 13), pulmonary embolus (n = 4), or both (n = 5). Using multiphasic (five or six phases; 19 patients) or standard (three patients with pulmonary embolus) ECG-gated, double spin-echo techniques, they were able to differentiate between causes of such abnormal signal patterns. The pattern of slow blood flow (abnormal signal in systole with fluctuating distribution during cardiac cycle, and intensity increasing visually from first to second echo) was noted in 89% of patients with pulmonary hypertension alone or in combination with pulmonary embolism, and was characteristic of high systolic pulmonary pressures (12 of 12 patients with pressure > 80 mm Hg, vs. 3 of 5 patients with pressure 55 mm Hg vs. 5 of 7 patients with pressures <55 mm Hg). This pattern was differentiated from that of thrombus (persistent signal with fixed distribution during cardiac cycle, and little to no visible intensity change from first to second echo), which was noted in six of seven proved embolus cases. Thus, gated multiphase MR imaging shows potential for the noninvasive visualization of pulmonary embolus and the differentiation of this entity from the slow blood flow of pulmonary hypertension

  14. Two dimensional polar display of cardiac blood pool SPECT

    International Nuclear Information System (INIS)

    Honda, Norinari; Machida, Kikuo; Mamiya, Toshio; Takahashi, Taku; Takishima, Teruo; Hasegawa, Noriko; Hashimoto, Masanori; Ohno, Ken

    1989-01-01

    A new method of ECG gated cardiac blood pool SPECT to illustrate the left ventricular (LV) wall motion in a single static image, two dimensional polar display (2DPD), was described. Circumferential profiles of the difference between end diastolic and end systolic short axis images of the LV were displayed in a similar way to the bull's eye plot of 201 Tl myocardial SPECT. The diagnoses by 2DPDs agreed with those by cinematic displays of ECG gated blood pool SPECT in 74 out of 84 segments (85.5%) of abnormal motion, and 155 out of 168 segments (80.3%) of normal motion. It is concluded that 2DPD can evaluate regional wall motion by a single static image in a significant number of patients, and is also useful in comparing with the bull's eye image of 201 Tl myorcardial SPECT. (orig.)

  15. ECG gated NMR-CT for cardiovascular diseases

    International Nuclear Information System (INIS)

    Nishikawa, J.; Machida, K.; Iio, M.; Yoshimoto, N.; Sugimoto, T.; Kawaguchi, H.; Mano, H.

    1984-01-01

    The authors applied NMR-CT to cardiac study with ECG gated technique to evaluate the left ventricular (LV) function and compared it with cardiovascular nuclear medicine study (NM). The NMR-CT machine has resistive air-core magnet with 0.15 Tesla. The saturation recovery image or inversion recovery image were obtained as 256 x 256 matrix and 15 mm in thickness. The study population was ten patients who were evaluated both by NMR image and by NM performed within one week interval. The heart muscle was able to be visualized without any contrast material nor radioisotopes in inversion recovery images, whereas saturation recovery images failed to separate heart muscle from blood pool. The wall motions of LV in both methods were well correlated except for inferior wall. The values of ejection fraction in NMR image were moderately low, but two modalities showed satisfactory correlation (r=0.85). The region of myocardial infarction was revealed as wall thinning and/or wall motion abnormality. It is still preliminary to draw a conclusion, however, it can be said that in the evaluation of LV function, method by NMR might be of equal value to those of NM. It can be certain that eventually gated NMR-CT will become more effective method for various aspects of cardiovascular evaluation

  16. Simultaneous ECG-gated PET imaging of multiple mice

    International Nuclear Information System (INIS)

    Seidel, Jurgen; Bernardo, Marcelino L.; Wong, Karen J.; Xu, Biying; Williams, Mark R.; Kuo, Frank; Jagoda, Elaine M.; Basuli, Falguni; Li, Changhui; Griffiths, Gary L.

    2014-01-01

    Introduction: We describe and illustrate a method for creating ECG-gated PET images of the heart for each of several mice imaged at the same time. The method is intended to increase “throughput” in PET research studies of cardiac dynamics or to obtain information derived from such studies, e.g. tracer concentration in end-diastolic left ventricular blood. Methods: An imaging bed with provisions for warming, anesthetic delivery, etc., was fabricated by 3D printing to allow simultaneous PET imaging of two side-by-side mice. After electrode attachment, tracer injection and placement of the animals in the scanner field of view, ECG signals from each animal were continuously analyzed and independent trigger markers generated whenever an R-wave was detected in each signal. PET image data were acquired in “list” mode and these trigger markers were inserted into this list along with the image data. Since each mouse is in a different spatial location in the FOV, sorting of these data using trigger markers first from one animal and then the other yields two independent and correctly formed ECG-gated image sequences that reflect the dynamical properties of the heart during an “average” cardiac cycle. Results: The described method yields two independent ECG-gated image sequences that exhibit the expected properties in each animal, e.g. variation of the ventricular cavity volumes from maximum to minimum and back during the cardiac cycle in the processed animal with little or no variation in these volumes during the cardiac cycle in the unprocessed animal. Conclusion: ECG-gated image sequences for each of several animals can be created from a single list mode data collection using the described method. In principle, this method can be extended to more than two mice (or other animals) and to other forms of physiological gating, e.g. respiratory gating, when several subjects are imaged at the same time

  17. ECG-gating in non-cardiac digital subtraction angiography

    International Nuclear Information System (INIS)

    Gattoni, F.; Baldini, V.; Cairo, F.

    1987-01-01

    This paper reports the results of the ECG-gating in non-cardiac digital subtraction angiography (DSA). One hundred and fifteen patients underwent DSA (126 examinations); ECG-gating was applied in 66/126 examinations: images recorded at 70% of R wave were subtracted. Artifacts produced by vascular movements were evaluated in all patients: only 40 examinations, carried out whithout ECG-gating, showed vascular artifacts. The major advantage of the ECG-gated DSA is the more efficent subtraction because of the better images superimposition: therefore, ECG-gating can be clinically helpful. On the contrary, it could be a problem in arrhytmic or bradycardic patients. ECG-gating is helpful in DSA imaging of the thoracic and abdominal aorta and of the cervical and renal arteries. In the examinations of peripheral vessels of the limbs it is not so efficent as in the trunk or in the neck

  18. Visualization of neonatal coronary arteries on multidetector row CT: ECG-gated versus non-ECG-gated technique

    International Nuclear Information System (INIS)

    Tsai, I.C.; Lee, Tain; Chen, Min-Chi; Fu, Yun-Ching; Jan, Sheng-Lin; Wang, Chung-Chi; Chang, Yen

    2007-01-01

    Multidetector CT (MDCT) seems to be a promising tool for detection of neonatal coronary arteries, but whether the ECG-gated or non-ECG-gated technique should be used has not been established. To compare the detection rate and image quality of neonatal coronary arteries on MDCT using ECG-gated and non-ECG-gated techniques. Twelve neonates with complex congenital heart disease were included. The CT scan was acquired using an ECG-gated technique, and the most quiescent phase of the RR interval was selected to represent the ECG-gated images. The raw data were then reconstructed without the ECG signal to obtain non-ECG-gated images. The detection rate and image quality of nine coronary artery segments in the two sets of images were then compared. A two-tailed paired t test was used with P values <0.05 considered as statistically significant. In all coronary segments the ECG-gated technique had a better detection rate and produced images of better quality. The difference between the two techniques ranged from 25% in the left main coronary artery to 100% in the distal right coronary artery. For neonates referred for MDCT, if evaluation of coronary artery anatomy is important for the clinical management or surgical planning, the ECG-gated technique should be used because it can reliably detect the coronary arteries. (orig.)

  19. Multi detector computed tomography (MDCT) of the aortic root; ECG-gated verses non-ECG-gated examinations

    International Nuclear Information System (INIS)

    Kristiansen, Joanna; Guenther, Anne; Aalokken, Trond Mogens; Andersen, Rune

    2011-01-01

    Purpose: Motion artifacts may degrade a conventional CT examination of the ascending aorta and hinder accurate diagnosis. We quantitatively compared retrospectively electrocardiographic (ECG) -gated multi detector computed tomography (MDCT) with non-ECG-gated MDCT in order to demonstrate whether or not one of the methods should be preferred. Method: The study included seventeen patients with surgically reconstructed aortic root and reimplanted coronary arteries. All patients had undergone both non-gated MDCT and retrospectively ECG-gated MDCT employing a stringently modulated tube current with single phase image reconstruction. The incidence of motion artifacts in the left main coronary artery (LM), proximal right coronary artery (RCA), and aortic root and ascending aorta were rated using a four point scale. The effective dose for each scan was calculated and normalized to a 15 cm scan length. Statistical analysis of motion artifacts and radiation dose was performed using Wilcoxon matched pairs signed rank sum test. Results: A significant reduction in motion artifacts was found in all three vessels in images from the retrospectively ECG-gated scans (LM: P = 0.005, RCA: P = 0.015, aorta: P = 0.003). The mean normalized effective radiation dose was 3.69 mSv (±1.03) for the non-ECG-gated scans and 16.37 mSv (±2.53) for the ECG-gated scans. Conclusion: Retrospective ECG-gating with single phase reconstruction significantly reduces the incidence of motion artifacts in the aortic root and the proximal portion of the coronary arteries but at the expense of a fourfold increase in radiation dose.

  20. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    International Nuclear Information System (INIS)

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T.

    2004-01-01

    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P [de

  1. Parametric tomography of the cardiac blood pool

    International Nuclear Information System (INIS)

    Meyer, M.; Schwartz, K.D.

    1990-01-01

    In nuclear cardiology image processing is performed usually in 3 of 4 dimensions. ECG-gated SPECT (GSPECT) would make it possible to obtain all 4 dimensions of space and time during one examination, but its duration as well as radiation dose is limited resulting in a low signal-to-noise ratio. Sensitive feature extractions from the amount of data are necessary, e.g. Fourier filtering or extracting isovolumetric intervals. The relatively large amount of calculations and storage requirements often handicaps tomographic ventriculography because a high number of sections have to be processed and the temporal resolution is limited. A new list-mode oriented tomographic algorithm demands less storage and fewer calculations: The Fourier coefficient extraction and the filtered back projection, both of which are linear operations, could be interchanged in the case of thoracic SPECT. The feature extraction algorithm process internal list-mode heart cycles for discrimination of invalid cycles, for end-diastolic and end-systolic synthesis as well as for Fourier analysis of the first harmonic in 10 ms steps. Reconstruction operations are applied also to modified distribution matrices of Fourier coefficients. By only processing 4 spatial matrix sequences (end-diastolic and end-systolic images, amplitude and phase values) parametric tomography becomes practicable and could be also performed by a minicomputer with 64 KByte memory in addition to the possibilities of the planar left ventricular gated imaging. If there are 3 or more processors available a complete feature extraction on-the-fly will be possible. The numerical algorithms were tested with respect to stable reconstructions by phantoms. First results of a patient examination are used to explore effective display techniques, and preliminary modes are demonstrated. It is the purpose of this study to obtain additional information about the gated planar cardiac blood pool imaging in the field of SPECT. (author)

  2. ECG-gated myocardial imaging with 201Tl

    International Nuclear Information System (INIS)

    Baehre, M.

    1980-01-01

    ECG-gated myocardial scintigraphy by means of 201 TI was performed in 11 patients. Good scintigrams could be gained by using long imaging times, but there was no additional information when compared with static images. Disadvantages were long imaging time, higher technical expenditure, and the smaller number of projections. Furthermore, there is no possibility of performing myocardial imaging under stress. (orig.) [de

  3. Measurement of ventricular function by ECG gating during atrial fibrillation

    International Nuclear Information System (INIS)

    Bacharach, S.L.; Green, M.V.; Bonow, R.O.; Findley, S.L.; Ostrow, H.G.; Johnston, G.S.

    1981-01-01

    The assumptions necessary to perform ECG-gated cardiac studies are seemingly not valid for patients in atrial fibrillation (AF). To evaluate the effect of AF on equilibrium gated scintigraphy, beat-by-beat measurements of left-ventricular function were made on seven subjects in AF (mean heart rate 64 bpm), using a high-efficiency nonimaging detector. The parameters evaluated were ejection fraction (EF), time to end-systole (TES), peak rates of ejection and filling (PER,PFR), and their times of occurrence (TPER, TPFR). By averaging together single-beat values of EF, PER, etc., it was possible to determine the true mean values of these parameters. The single-beam mean values were compared with the corresponding parameters calculated from one ECG-gated time-activity curve (TAC) obtained by superimposing all the single-beat TACs irrespective of their length. For this population with slow heart rates, we find that the values for EF, etc., produced from ECG-gated time-activity curves, are very similar to those obtained from the single-beat data. Thus use of ECG gating at low heart rates may allow reliable estimation of average cardiac function even in subjects with AF

  4. Automatic extraction of left ventricular mass and volumes using parametric images from non-ECG-gated 15O-water PET/CT

    DEFF Research Database (Denmark)

    Nordström, J; Harms, Hans; Lubberink, Mark

    of the present study was to investigate the feasibility of measuring LV geometry using dynamic 15O-water PET/CT without ECG-gating. Methods: Parametric images of MBF, perfusable tissue fraction (PTF) and LV blood pool were generated automatically using kinetic modelling. Segmentation of the LV wall using PTF......Introduction: 15O-water positron emission tomography (PET) is considered the gold standard for non-invasive quantification of myocardial blood flow (MBF). It has been shown to identify patients with significant coronary artery disease (CAD) with high accuracy. Hypertrophy with or without dilatation...... combined to measure stroke volume (SV=EDV-ESV) and ejection fraction (EF=SV/EDV). Accuracy was determined by comparing PET to cardiac magnetic resonance (CMR) in 30 asymptomatic patients with high grade LV regurgitation (group A). Precision was determined as inter-observer variation in group...

  5. Optimization of Ecg Gating in Quantitative Femoral Angiography

    International Nuclear Information System (INIS)

    Nilsson, S.; Berglund, I.; Erikson, U.; Johansson, J.; Walldius, G.

    2003-01-01

    Purpose: To determine which phase of the heart cycle would yield the highest reproducibility in measuring atherosclerosis-related variables such as arterial lumen volume and edge roughness. Material and Methods: 35 patients with hypercholesterolemia underwent select ive femoral angiography, repeated four times at 10-min intervals. The angiographies were performed with Ecg-gated exposures. In angiographies 1 and 2 the delay from R-wave maximum to each exposure was 0.1 s, in angiographies 3 and 4 the delay was 0.1, 0.3, 0.5 or 0.7 s or the exposures were performed 1/s without Ecg gating. Arterial lumen volume and edge roughness were measured in a 20-cm segment of the superficial femoral artery using a computer-based densitometric method. Measurement reproducibility was determined by comparing angiographies 1-2 and angiographies 3-4. Results: When measuring arterial lumen volume and edge roughness of a 20-cm segment of the femoral artery, reproducibility was not dependent on Ecg gating. In measuring single arterial diameters and cross-sectional areas, the reproducibility was better when exposures were made 0.1 s after the R-wave maximum than when using other settings of the Ecg gating device or without Ecg gating. Conclusion: The influence of pulsatile flow upon quantitative measurement in femoral angiograms seems to be the smallest possible in early systole, as can be demonstrated when measuring single diameters and cross-sectional areas. In variables based on integration over longer segments, measurement reproducibility seems to be independent of phase

  6. Optimization of Ecg Gating in Quantitative Femoral Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, S.; Berglund, I.; Erikson, U. [Univ. Hospital, Uppsala (Sweden). Dept. of Oncology, Radiology and Clinical Immunology; Johansson, J.; Walldius, G. [Karolinska Hospital, Stockholm (Sweden). King Gustav V Research Inst.

    2003-09-01

    Purpose: To determine which phase of the heart cycle would yield the highest reproducibility in measuring atherosclerosis-related variables such as arterial lumen volume and edge roughness. Material and Methods: 35 patients with hypercholesterolemia underwent select ive femoral angiography, repeated four times at 10-min intervals. The angiographies were performed with Ecg-gated exposures. In angiographies 1 and 2 the delay from R-wave maximum to each exposure was 0.1 s, in angiographies 3 and 4 the delay was 0.1, 0.3, 0.5 or 0.7 s or the exposures were performed 1/s without Ecg gating. Arterial lumen volume and edge roughness were measured in a 20-cm segment of the superficial femoral artery using a computer-based densitometric method. Measurement reproducibility was determined by comparing angiographies 1-2 and angiographies 3-4. Results: When measuring arterial lumen volume and edge roughness of a 20-cm segment of the femoral artery, reproducibility was not dependent on Ecg gating. In measuring single arterial diameters and cross-sectional areas, the reproducibility was better when exposures were made 0.1 s after the R-wave maximum than when using other settings of the Ecg gating device or without Ecg gating. Conclusion: The influence of pulsatile flow upon quantitative measurement in femoral angiograms seems to be the smallest possible in early systole, as can be demonstrated when measuring single diameters and cross-sectional areas. In variables based on integration over longer segments, measurement reproducibility seems to be independent of phase.

  7. Impact of ECG gating in contrast-enhanced MR angiography for the assessment of the pulmonary veins and the left atrium anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, M.; Buecker, A.; Muehlenbruch, G.; Guenther, R.W.; Spuentrup, E. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum RWTH Aachen (Germany); Schauerte, P. [Medizinische Klinik 1, Universitaetsklinikum RWTH Aachen (Germany)

    2006-02-15

    Purpose: Implementation of ECG gating in contrast-enhanced MR angiography (ceMRA) for improved visualization of the pulmonary veins, the left atrium, and the thoracic vessels. Materials and Methods: CeMRA was performed on twelve patients with a history of recurrent atrial fibrillation for the purpose of an intra-individual comparison with and without ECG gating on a 1.5 Tesla MR system (Gyroscan Intera, Philips Medical Systems, Best, NL). Objective image quality parameters such as the signal-to-noise ratio (SNR) of the blood and the contrast-to-noise ratio (CNR) between the blood and myocardium or lung parenchyma were analyzed. The contour sharpness of the pulmonary veins, left atrium, ascending aorta, and pulmonary trunk was also measured. In addition, the artifact level was subjectively assessed by two observers blinded with respect to the sequence parameters. Statistically significant differences (p<0.05) between the procedures were analyzed using the Wilcoxon test and Pearson Chi-square test. Results: The use of ECG gating in ceMRA significantly reduced artifacts caused by cardiac motion and vessel pulsation. This in turn lead to a significant increase in the contour sharpness of the left atrium and the thoracic vessels. In addition, higher SNR and CNR were found using ECG-gated ceMRA compared to standard ceMRA. Conclusion: The use of ECG gating in ceMRA results in artifact-free and sharper delineation of the structures of the heart and thoracic vessels. (orig.)

  8. Impact of ECG gating in contrast-enhanced MR angiography for the assessment of the pulmonary veins and the left atrium anatomy

    International Nuclear Information System (INIS)

    Katoh, M.; Buecker, A.; Muehlenbruch, G.; Guenther, R.W.; Spuentrup, E.; Schauerte, P.

    2006-01-01

    Purpose: Implementation of ECG gating in contrast-enhanced MR angiography (ceMRA) for improved visualization of the pulmonary veins, the left atrium, and the thoracic vessels. Materials and Methods: CeMRA was performed on twelve patients with a history of recurrent atrial fibrillation for the purpose of an intra-individual comparison with and without ECG gating on a 1.5 Tesla MR system (Gyroscan Intera, Philips Medical Systems, Best, NL). Objective image quality parameters such as the signal-to-noise ratio (SNR) of the blood and the contrast-to-noise ratio (CNR) between the blood and myocardium or lung parenchyma were analyzed. The contour sharpness of the pulmonary veins, left atrium, ascending aorta, and pulmonary trunk was also measured. In addition, the artifact level was subjectively assessed by two observers blinded with respect to the sequence parameters. Statistically significant differences (p<0.05) between the procedures were analyzed using the Wilcoxon test and Pearson Chi-square test. Results: The use of ECG gating in ceMRA significantly reduced artifacts caused by cardiac motion and vessel pulsation. This in turn lead to a significant increase in the contour sharpness of the left atrium and the thoracic vessels. In addition, higher SNR and CNR were found using ECG-gated ceMRA compared to standard ceMRA. Conclusion: The use of ECG gating in ceMRA results in artifact-free and sharper delineation of the structures of the heart and thoracic vessels. (orig.)

  9. Utility of Electrocardiography (ECG)-Gated Computed Tomography (CT) for Preoperative Evaluations of Thymic Epithelial Tumors.

    Science.gov (United States)

    Ozawa, Yoshiyuki; Hara, Masaki; Nakagawa, Motoo; Shibamoto, Yuta

    2016-01-01

    Preoperative evaluation of invasion to the adjacent organs is important for the thymic epithelial tumors on CT. The purpose of our study was to evaluate the utility of electrocardiography (ECG)-gated CT for assessing thymic epithelial tumors with regard to the motion artifacts produced and the preoperative diagnostic accuracy of the technique. Forty thymic epithelial tumors (36 thymomas and 4 thymic carcinomas) were examined with ECG-gated contrast-enhanced CT using a dual source scanner. The scan delay after the contrast media injection was 30 s for the non-ECG-gated CT and 100 s for the ECG-gated CT. Two radiologists blindly evaluated both the non-ECG-gated and ECG-gated CT images for motion artifacts and determined whether the tumors had invaded adjacent structures (mediastinal fat, superior vena cava, brachiocephalic veins, aorta, pulmonary artery, pericardium, or lungs) on each image. Motion artifacts were evaluated using a 3-grade scale. Surgical and pathological findings were used as a reference standard for tumor invasion. Motion artifacts were significantly reduced for all structures by ECG gating ( p =0.0089 for the lungs and p ECG-gated CT and ECG-gated CT demonstrated 79% and 95% accuracy, respectively, during assessments of pericardial invasion ( p =0.03). ECG-gated CT reduced the severity of motion artifacts and might be useful for preoperative assessment whether thymic epithelial tumors have invaded adjacent structures.

  10. MR flow measurements for assessment of the pulmonary, systemic and bronchosystemic circulation: Impact of different ECG gating methods and breathing schema

    International Nuclear Information System (INIS)

    Ley, Sebastian; Ley-Zaporozhan, Julia; Kreitner, Karl-Friedrich; Iliyushenko, Svitlana; Puderbach, Michael; Hosch, Waldemar; Wenz, Heiner; Schenk, Jens-Peter; Kauczor, Hans-Ulrich

    2007-01-01

    Purpose: Different ECG gating techniques are available for MR phase-contrast (PC) flow measurements. Until now no study has reported the impact of different ECG gating techniques on quantitative flow parameters. The goal was to evaluate the impact of the gating method and the breathing schema on the pulmonary, systemic and bronchosystemic circulation. Material and methods: Twenty volunteers were examined (1.5 T) with free breathing phase-contrast flow (PC-flow) measurements with prospective (free-prospective) and retrospective (free-retrospective) ECG gating. Additionally, expiratory breath-hold retrospective ECG gated measurements (bh-retrospective) were performed. Blood flow per minute; peak velocity and time to peak velocity were compared. The clinically important difference between the systemic and pulmonary circulation (bronchosystemic shunt) was calculated. Results: Blood flow per minute was lowest for free-prospective (6 l/min, pulmonary trunc) and highest for bh-retrospective measurements (6.9 l/min, pulmonary trunc). No clinically significant difference in peak velocity was assessed (82-83 cm/s pulmonary trunc, 109-113 cm/s aorta). Time to peak velocity was shorter for retro-gated free-retrospective and bh-retrospective than for pro-gated free-prospective. The difference between systemic and pulmonary measurements was least for the free-retrospective technique. Conclusion: The type of gating has a significant impact on flow measurements. Therefore, it is important to use the same ECG gating method, especially for follow-up examinations. Retrospective ECG gated free breathing measurements allow for the most precise assessment of the bronchosystemic blood flow and should be used in clinical routine

  11. ECG gated magnetic resonance imaging in cardiovascular disease

    International Nuclear Information System (INIS)

    Park, Jae Hyung; Im, Chung Kie; Han, Man Chung; Kim, Chu Wan

    1985-01-01

    Using KAIS 0.15 Tesla resistive magnetic imaging system, ECG gated magnetic resonance (MR) image of various cardiovascular disease was obtained in 10 patients. The findings of MR image of the cardiovascular disease were analysed and the results were as follows: 1. In 6 cases of acquired and congenital cardiac diseases, there were 2 cases of myocardial infarction, 1 case of mitral stenosis and 3 cases of corrected transportation of great vessels. The others were 3 cases of aortic disease and 1 case of pericardial effusion with lymphoma. 2. Myocardial thinning and left ventricular aneurysm were detected in MR images of myocardial infarction. The left atrium was well delineated and enlarged in the case of mitral stenosis. And segmental analysis was possible in the cases of corrected transposition since all cardiac structures were well delineated anatomically. 3. In aortic diseases, the findings of MR image were enlarged lumen, compressed cardiac chambers in ascending aortic aneurysm, intimal flap, enhanced false lumen in dissecting aneurysm and irregular narrowing of aorta with arterial obstruction in Takayasu's arteritis. 4. Pericardial effusion revealed a conspicuous contrast with neighboring mediastinal fat and cardiac wall due to it low signal encircling cardiac wall. 5. ECG gated MR image is an accurate non-invasive imaging modality for the diagnosis of cardiovascular disease and better results of its clinical application are expected in the future with further development in the imaging system and more clinical experiences

  12. Assessment of hypertrophic cardiomyopathy by ECG gated cardiac computed tomography

    International Nuclear Information System (INIS)

    Takeuchi, Kazuhide; Tanaka, Chujiro; Oku, Hisao

    1981-01-01

    The applicability of ECG gated cardiac computed tomography (CT) in 12 patients with hypertrophic cardiomyopathy was examined. Six of the 12 patients had hypertrophic obstructive cardiomyopathy, including one patient with mid-ventricular obstruction. Three of the 12 patients had hypertrophic non-obstructive cardiomyopathy, and three had apical hypertrophic cardiomyopathy. The diagnosis of hypertrophic cardiomyopathy was confirmed by the angiocardiogram in all patients. Cardiac CT was performed after intravenous administration of contrast media usually given as a bolus injection. The gantry was set with positive 20 0 tilt angle. In all patients with hypertrophic obstructive cardiomyopathy except for mid-ventricular obstruction, the hypertrophied interventricular septum in the basal and mid portions was observed, and the left ventricular cavity was narrowed in systole. In a patient with mid-ventricular obstruction, the marked hypertrophied interventricular septum and antero-lateral papillary muscle were observed. In diastole, the left ventricular cavity was narrow and divided into two parts. The apical cavity was completely disappeared in systole. In all patients with hypertrophic non-obstructive cardiomyopathy, the diffuse hypertrophied interventricular septum was observed in diastole. In systole, the apical portion of the left ventricular cavity was markedly narrow and antero-lateral papillary muscle was hypertrophic. In all patients with apical hypertrophic cardiomyopathy, the marked apical hypertrophy of the left ventricular wall was observed in diastole. It is concluded that ECG gated cardiac CT could estimate myocardial wall motion and thickness and differentiate the types of hypertrophic cardiomyopathy each other. (author)

  13. ECG-gated scintillation probe measurement of left ventricular function

    International Nuclear Information System (INIS)

    Bacharach, S.L.; Green, M.V.; Borer, J.S.; Ostrow, H.G.; Redwood, D.R.; Johnston, G.S.

    1977-01-01

    A nonimaging, ECG-gated scintillation-probe system is described that permits real-time quantification, at high temporal resolution, of the time variation of left ventricular (LV) volume over a complete, average cardiac cycle. Linearity between counting rate and volume, probe positioning, and background correction were investigated for both cylindrically collimated (CC) and parallel-hole-collimated (PC) detectors. In 53 patient studies, results obtained with these probes were compared with results obtained from an ECG-gated gamma camera system (CS) with high temporal resolution. Time-activity curves obtained by all three devices were essentially identical in shape (for CC against CS, r = 0.93; for PC against CS, r = 0.98) and in intracycle timing. Left-ventricular ejection fractions obtained with the probes showed workable agreement with the camera: for CC against CS, r = 0.85 (N = 31); for PC against CS, r = 0.90 (N = 21). When LV background is removed as a source of error, the correlation between (PC) probe and camera is improved (r = 0.95, N = 21). This suggests that the portable probe system be used in circumstances where exact knowledge of LV background is minimally important--e.g., continuous bedside monitoring of changes in LV function

  14. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Bastarrika, Gorka [Dept. of Radiology, Clinica Univ. de Navarra, Pamplona (Spain); Cardiac Imaging Unit, Clinica Univ. de Navarra, Pamplona (Spain)], e-mail: bastarrika@unav.es

    2012-06-15

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 {+-} 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 {+-} 58.3 mL) with respect to ECG-gated CT (142.7 {+-} 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 {+-} 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols.

  15. Feasibility of epicardial adipose tissue quantification in non-ECG-gated low-radiation-dose CT: comparison with prospectively ECG-gated cardiac CT

    International Nuclear Information System (INIS)

    Simon-Yarza, Isabel; Viteri-Ramirez, Guillermo; Saiz-Mendiguren, Ramon; Slon-Roblero, Pedro J.; Paramo, Maria; Bastarrika, Gorka

    2012-01-01

    Background: Epicardial adipose tissue (EAT) is an important indicator of cardiovascular risk. This parameter is generally assessed on ECG-gated computed tomography (CT) images. Purpose: To evaluate feasibility and reliability of EAT quantification on non-gated thoracic low-radiation-dose CT examinations with respect to prospectively ECG-gated cardiac CT acquisition. Material and Methods: Sixty consecutive asymptomatic smokers (47 men; mean age 64 ± 9.8 years) underwent low-dose CT of the chest and prospectively ECG-gated cardiac CT acquisitions (64-slice dual-source CT). The two examinations were reconstructed with the same range, field of view, slice thickness, and convolution algorithm. Two independent observers blindly quantified EAT volume using commercially available software. Data were compared with paired sample Student t-test, concordance correlation coefficients (CCC), and Bland-Altman plots. Results: No statistically significant difference was observed for EAT volume quantification with low-dose-CT (141.7 ± 58.3 mL) with respect to ECG-gated CT (142.7 ± 57.9 mL). Estimation of CCC showed almost perfect concordance between the two techniques for EAT-volume assessment (CCC, 0.99; mean difference, 0.98 ± 5.1 mL). Inter-observer agreement for EAT volume estimation was CCC: 0.96 for low-dose-CT examinations and 0.95 for ECG-gated CT. Conclusion: Non-gated low-dose CT allows quantifying EAT with almost the same concordance and reliability as using dedicated prospectively ECG-gated cardiac CT acquisition protocols

  16. Clinical application of ECG-gated 256-slice CT angiography for diagnosis of congenital heart disease

    International Nuclear Information System (INIS)

    Tian Xinhua; Liu Jianhua; Gong Tingting; Geng Lili; Sun Yong

    2011-01-01

    Objective: To investigate the clinical application of ECG-gated 256-slice CT angiography for diagnosis of congenital heart disease, and to evaluate the relationship of the image quality and radiation dose between prospective ECG-gated and retrospective ECG-gated cardiac CT angiography (CTA). Methods: Sixty patients who doubt congenital heart disease underwent cardiac CTA, and they were randomly divided into two groups. Thirty patients in group A underwent prospective ECG-gated cardiac CTA, and thirty patients in group B underwent retrospective ECG-gated cardiac CTA. Then the homogeneous enhancement of vascular structures, stair-step artifact, overall image quality and radiation dose were evaluated. Results: The homogeneous enhancement of vascular structures were 2.8±0.3 and 2.7±0.6, respectively, in two groups; and there was no statistical significance (P>0.05). The stair-step artifact were 3.0±0.9 and 3.1±0.9, respectively, in two groups; and there was also no statistical significance (P>0.05). The overall image quality were 3.0±0.8 and 3.1±0.9, respectively, in two group; and there was statistical significance (P>0.05). However, the effective dose were (5.24±0.52) mSv and (16.68±1.49) mSv, respectively, in two groups; and there was statistical significance (P<0.001). Conclusion: Compared with retrospective ECG-gated cardiac CTA, prospective ECG-gated cardiac CTA can reduce radiation dose about 68.6% , while maintaining the image quality which could be made diagnosis. (authors)

  17. ECG-gated computed tomography: a new role for patients with suspected aortic prosthetic valve endocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Fagman, Erika; Flinck, Agneta; Lamm, Carl [Sahlgrenska University Hospital, Department of Radiology, Gothenburg (Sweden); Perrotta, Sossio [Sahlgrenska University Hospital, Department of Cardiovascular Surgery and Anaesthesia, Gothenburg (Sweden); Bech-Hanssen, Odd [Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg (Sweden); Sahlgrenska University Hospital, Department of Cardiology, Gothenburg (Sweden); Olaison, Lars [Sahlgrenska University Hospital, Department of Infectious Diseases, Gothenburg (Sweden); Svensson, Gunnar [Sahlgrenska University Hospital, Department of Cardiovascular Surgery and Anaesthesia, Gothenburg (Sweden); The Sahlgrenska Academy at the University of Gothenburg, Department of Molecular and Clinical Medicine, Institute of Medicine, Gothenburg (Sweden)

    2012-11-15

    The aim of this prospective study was to investigate the agreement in findings between ECG-gated CT and transoesophageal echocardiography (TEE) in patients with aortic prosthetic valve endocarditis (PVE). Twenty-seven consecutive patients with PVE underwent 64-slice ECG-gated CT and TEE and the results were compared. Imaging was compared with surgical findings (surgery was performed in 16 patients). TEE suggested the presence of PVE in all patients [thickened aortic wall (n = 17), vegetation (n = 13), abscess (n = 16), valvular dehiscence (n = 10)]. ECG-gated CT was positive in 25 patients (93 %) [thickened aortic wall (n = 19), vegetation (n = 7), abscess (n = 18), valvular dehiscence (n = 7)]. The strength of agreement [kappa (95 % CI)] between ECG-gated CT and TEE was very good for thickened wall [0.83 (0.62-1.0)], good for abscess [0.68 (0.40-0.97)] and dehiscence [0.75 (0.48-1.0)], and moderate for vegetation [0.55 (0.26-0.88)]. The agreement was good between surgical findings (abscess, vegetation and dehiscence) and imaging for ECG-gated CT [0.66 (0.49-0.87)] and TEE [0.79 (0.62-0.96)] and very good for the combination of ECG-gated CT and TEE [0.88 (0.74-1.0)]. Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE. (orig.)

  18. ECG-gated computed tomography: a new role for patients with suspected aortic prosthetic valve endocarditis

    International Nuclear Information System (INIS)

    Fagman, Erika; Flinck, Agneta; Lamm, Carl; Perrotta, Sossio; Bech-Hanssen, Odd; Olaison, Lars; Svensson, Gunnar

    2012-01-01

    The aim of this prospective study was to investigate the agreement in findings between ECG-gated CT and transoesophageal echocardiography (TEE) in patients with aortic prosthetic valve endocarditis (PVE). Twenty-seven consecutive patients with PVE underwent 64-slice ECG-gated CT and TEE and the results were compared. Imaging was compared with surgical findings (surgery was performed in 16 patients). TEE suggested the presence of PVE in all patients [thickened aortic wall (n = 17), vegetation (n = 13), abscess (n = 16), valvular dehiscence (n = 10)]. ECG-gated CT was positive in 25 patients (93 %) [thickened aortic wall (n = 19), vegetation (n = 7), abscess (n = 18), valvular dehiscence (n = 7)]. The strength of agreement [kappa (95 % CI)] between ECG-gated CT and TEE was very good for thickened wall [0.83 (0.62-1.0)], good for abscess [0.68 (0.40-0.97)] and dehiscence [0.75 (0.48-1.0)], and moderate for vegetation [0.55 (0.26-0.88)]. The agreement was good between surgical findings (abscess, vegetation and dehiscence) and imaging for ECG-gated CT [0.66 (0.49-0.87)] and TEE [0.79 (0.62-0.96)] and very good for the combination of ECG-gated CT and TEE [0.88 (0.74-1.0)]. Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE. (orig.)

  19. Refined staging in hilar bronchial neoplasms with ECG-gated multislice-CT. Case report

    International Nuclear Information System (INIS)

    Ohlmann, S.; Daliri, A.; Froelich, J.J.; Nowak, R.; Michulla, R.

    2008-01-01

    Equivocal initial CT-based staging in 2 patients with hilar bronchial neoplasms was reassessed with retrospective ECG-gated Multislice-CT and optimized examination parameters prior to definition of treatment. An initially suspected irresectable T 4 tumor with mediastinal infiltration was downstaged to T 2 in one case, while tumor infiltration into the left atrium could be confirmed in the other case. In doubtful conditions, ECG-gated multislice CT with optimized examination parameters may be helpful for refined staging in patients with hilar bronchial neoplasma, thus possibly influencing treatment strategies. (orig.)

  20. Clinical blood pool MR Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leiner, Tim [Maastrich University Medical Center (Netherlands). Dept. of Radiology; Goyen, Martin [University Medical Center Hamburg-Eppendorf (Germany); Rohrer, Mathias [Bayer Schering Pharma AG, Berlin (Germany). European Business Unit Diagnostic Imaging; Schoenberg, Stefan O. (eds.) [University Hospital Mannheim Medical Faculty Mannheim - Heidelberg Univ. (Germany). Dept. of Clinical Radiology and Nuclear Medicine

    2008-07-01

    Clinical Blood Pool MR Imaging - This excellent treatise on Vasovist {sup registered} created by a team of exceptional faculty who are pioneers in MR Angiography covers the basic techniques, safety, efficacy, image processing and pharmaco-economic details to successfully implement a new level of MRA image quality with this new contrast agent. Martin Prince, Cornell University, New York The editors and authors have made groundbreaking contributions towards establishing MR angiography in various investigative settings, rendering it more precise and applying it for diverse indications. The work presented here is founded upon the extensive experience of the editors, as well as the broad range of experience from other scientific working groups. Maximilian Reiser, Ludwig Maximilian University, Munich Vasovist {sup registered} (Gadofosveset), worldwide the first blood pool agent, has only recently become available for clinical use, but has already gained wide acceptance as a tool to improve magnetic resonance angiography. This book presents the first in-depth introduction to the basic physicochemical aspects of the agent, the application of Vasovist {sup registered} in clinical MRA, as well as potential clinical applications beyond MRA and patient management-related aspects. The first part of the book explains basic and technical properties of the agent and the differences of Vasovist {sup registered} compared to currently available extracellular agents. The second part contains detailed chapters on safety and efficacy. In the third part the focus is on MR angiographic applications, and in the fourth part of the book potential clinical fields beyond MRA are explored. All clinical chapters feature ready-to-use clinical protocols and a series of take home messages that concisely summarize the current role of blood pool imaging for each specific indication. (orig.)

  1. Absolute quantitation of left ventricular wall and cavity parameters using ECG-gated PET

    DEFF Research Database (Denmark)

    Freiberg, Jacob; Hove, Jens D; Kofoed, Klaus F

    2004-01-01

    in a heart phantom and in healthy subjects. Twelve healthy men aged 64 +/- 8 years were studied by use of cine magnetic resonance imaging (MRI) and ECG-gated FDG-PET during euglycemic glucose-insulin clamp. At increasing image noise levels, the estimated cavity volume of the heart phantom was within 2 m...

  2. Cardiac blood pool emission tomography

    International Nuclear Information System (INIS)

    Itti, R.; Philippe, L.; Lorgeron, J.M.; Charbonnier, B.; Raynaud, P.; Brochier, M.

    1983-01-01

    After blood pool labeling using technetium-99m, a series of cardiac pictures is acquired during the rotation of a gamma-camera about the patient. Computer processing leads to reconstruction of various tomographic slices from the original planar projection. Electrocardiographic gating selects the different phases of the cardiac cycle. Individual slices through the left ventricular region are added in order to provide ''thick'' slices on which global and regional parameters of the left ventricular function can be determined. Due to the proportionality existing between count rates and labeled blood volumes, any geometrical model can be avoided. The delineation of regions of interest for count integration is made easier due to the absence of superimposition of structures; no correction for background is necessary. Tomography thus appears to be more consistent and more accurate than the classical methods using planar projections. In addition, right ventricular morphological and kinetic studies can be performed in the same conditions as for the left ventricle [fr

  3. ECG-gated multislice spiral CT for diagnosis of acute pulmonary embolism

    International Nuclear Information System (INIS)

    Marten, K.; Engelke, C.; Funke, M.; Obenauer, S.; Baum, F.; Grabbe, E.

    2003-01-01

    AIM: The purpose of this study was to determine the feasibility of echocardiogram (ECG)-gated multi-slice CT angiography (MCTA) in patients with clinical suspicion of acute venous thromboembolism (VTE), to investigate the effect of ECG-gating on cardiac motion artefacts, and to determine the diagnostic reader agreement of ECG-gated MCTA in comparison with conventional MCTA. MATERIALS AND METHODS: Forty-eight consecutive patients were prospectively enrolled and randomly underwent ECG-gated (n=25, group 1) or non-ECG-gated (n=23, group 2) eight-slice pulmonary MCTA. Image data were evaluated by three independent chest radiologists with respect to the presence or absence of emboli at different arterial levels (main, lobar, segmental, and subsegmental arteries), and with regard to cardiac motion artefacts. Statistical tests used to calculate inter-observer agreement were weighted κ statistics, extended κ statistics and confidence indices indicating three-reader agreement accuracy. RESULTS: Twenty-seven patients (56.3%) were diagnosed to have pulmonary embolism (13 from group 1, 14 from group 2). Cardiac motion artefacts were significantly more frequent in group 2 (70% in group 2 versus 13% in group 1, p=0.0001). The overall diagnostic agreement was excellent with both MCTA techniques (three-reader confidence index for all vascular territories: 0.76 and 0.84 for groups 1 and 2, respectively (extended κ=0.69 and 0.78, respectively); three-reader confidence index for diagnosis of VTE: 0.94 and 0.85 for groups 1 and 2, respectively (extended κ=0.91 and 0.73, respectively), weighted κ=0.81-0.83 and 0.92-0.95 for groups 1 and 2, respectively, and did not differ significantly between the two groups. In addition there was no significant difference of inter-observer agreement in either group at any assessed pulmonary arterial level. CONCLUSION: ECG-gated pulmonary MCTA is feasible in patients with clinical suspicion of VTE. However, ECG-gated image acquisition did not

  4. Step-and-shoot prospectively ECG-gated vs. retrospectively ECG-gated with tube current modulation coronary CT angiography using 128-slice MDCT patients with chest pain: diagnostic performance and radiation dose

    International Nuclear Information System (INIS)

    Kim, Jeong Su; Choo, Ki Seok; Jeong, Dong Wook

    2011-01-01

    Background With increasing awareness for radiation exposure, the study of diagnostic accuracy of coronary CT angiography (CCTA) with low radiation dose techniques is mandatory to both radiologist and clinician. Purpose To compare diagnostic performance and effective radiation dose between step-and-shoot prospectively ECG-gated and retrospectively ECG-gated with tube current modulation (TCM) CCTA using 128-slice multidetector computed tomography (MDCT). Material and Methods We retrospectively evaluated 60 patients who underwent CCTA with either of two different low-dose techniques using 128-slice MDCT (23 patients for step-and shoot-prospectively ECG-gated and 37 patients for retrospectively ECG-gated with TCM CCTA) followed by conventional coronary angiography. All coronary arteries and all segments thereof, except anatomical variants or small size (< 1.5 mm) ones, were included in analysis. Results In per-segment analysis, sensitivity, specificity, positive predictive value, and negative predictive value were 91/96%, 95/94%, 75/73%, and 98/99% for step-and-shoot prospectively ECG-gated and retrospectively ECG gated with TCM CCTA, respectively, relative to conventional coronary angiography. Effective radiation dose were 1.75 ± 0.83 mSv, 4.91 ± 1.71 mSv in the step-and-shoot prospectively ECG-gated and retrospectively ECG-gated with TCM CCTA groups, respectively. Conclusion The two low-radiation dose CCTA techniques using 128-slice MDCT yields comparable diagnostic performance for coronary artery disease in symptomatic patients with low heart rates

  5. Diagnostic accuracy of prospective ECG gated coronary computed tomography on a 256 slices scanner: Daily practice experience

    Directory of Open Access Journals (Sweden)

    Ahmed M. Fareed

    2014-03-01

    Conclusions: In a highly prevalence diseased population, prospective ECG-gated CTCA using 256-slice scanner is highly accurate for detection and quantification of the degree of coronary luminal stenosis in comparison to ICA.

  6. Prospective versus retrospective ECG-gated multislice CT coronary angiography: A systematic review of radiation dose and diagnostic accuracy

    International Nuclear Information System (INIS)

    Sun Zhonghua; Ng, Kwan-Hoong

    2012-01-01

    Purpose: To perform a systematic review of the radiation dose and diagnostic accuracy of prospective versus retrospective ECG-gated multislice CT coronary angiography. Materials and methods: A search of Pubmed/Medline and Sciencedirect databases for English literature was performed to identify studies comparing prospective and retrospective ECG-gated multislice CT angiography in the diagnosis of coronary artery disease. Effective dose, dose length product, image quality and diagnostic value were compared between two groups of studies. Results: 22 studies were included for analysis. The mean effective dose of prospective ECG-gated scans was 4.5 mSv (95% CI: 3.6, 5.3 mSv), which is significantly lower than that of retrospective scans, which is 13.8 mSv (95% CI: 11.5, 16.0 mSv) (p < 0.001). The mean dose length product was 225 mGy cm (95% CI: 188, 262 mGy cm) and 822 mGy cm (95% CI: 630, 1013 mGy cm) for the prospective and retrospective ECG-gated scans, respectively, indicating a statistically significant difference between these two protocols (p < 0.0001). The mean sensitivity and specificity of multislice CT angiography in the diagnosis of coronary artery disease was 97.7% (95% CI: 93.7%, 100%) and 92.1% (95% CI: 87.2%, 97%) for prospective ECG-gated scans; 95.2% (95% CI: 91%, 99.5%) and 94.4% (95% CI: 88.5%, 100%) for retrospective ECG-gated scans, respectively, with no significant difference for sensitivity but significant difference for specificity (p = 0.047). Conclusion: Multislice CT coronary angiography with prospective ECG-gating leads to a significant reduction of radiation dose when compared to that of retrospective ECG-gating, while offering comparable image quality and diagnostic value.

  7. Evaluation of coronary artery disease by helical CT using retrospective ECG-gating

    International Nuclear Information System (INIS)

    Kawawa, Yoko

    2001-01-01

    The purpose of this study is to evaluate the usefulness of helical CT using retrospective ECG-gating for visualization of the coronary artery and detection of coronary artery disease. We performed a coronary artery phantom study and established this new application, with 1-mm collimation, 1-mm table increment, and 0.1-mm reconstruction (0.8 sec/rotation). Helical CT of 31 patients with 39 coronary artery diseases (34 coronary artery stenoses, 1 vasospastic angina, 1 coronary artery dissection, 1 coronary artery ectasia and 2 coronary artery aneurysms) was performed in a single breath hold and ECG-gating without and with intravenous injection of nonionic iodine contrast material. We selected the images which were not affected by cardiac motion from the reconstruction images, in order to visualize the coronary artery for detection of coronary artery disease. The coronary artery was well visualized in 32 out of 39 vessels (82%). A good visualization of the coronary artery was correlated with the heart rate. Further, in this well visualized group, coronary artery diseases were detected in 24 out of 31 cases (77%). One case of vasospastic angina was not included. It was difficult to detect coronary artery disease in cases of heavily calcified vessels or in the left circumflex artery. Helical CT using this retrospective ECG-gating is a useful noninvasive examination for evaluation of coronary artery disease. (author)

  8. Residual motion compensation in ECG-gated interventional cardiac vasculature reconstruction

    International Nuclear Information System (INIS)

    Schwemmer, C; Müller, K; Hornegger, J; Rohkohl, C; Lauritsch, G

    2013-01-01

    Three-dimensional reconstruction of cardiac vasculature from angiographic C-arm CT (rotational angiography) data is a major challenge. Motion artefacts corrupt image quality, reducing usability for diagnosis and guidance. Many state-of-the-art approaches depend on retrospective ECG-gating of projection data for image reconstruction. A trade-off has to be made regarding the size of the ECG-gating window. A large temporal window is desirable to avoid undersampling. However, residual motion will occur in a large window, causing motion artefacts. We present an algorithm to correct for residual motion. Our approach is based on a deformable 2D–2D registration between the forward projection of an initial, ECG-gated reconstruction, and the original projection data. The approach is fully automatic and does not require any complex segmentation of vasculature, or landmarks. The estimated motion is compensated for during the backprojection step of a subsequent reconstruction. We evaluated the method using the publicly available CAVAREV platform and on six human clinical datasets. We found a better visibility of structure, reduced motion artefacts, and increased sharpness of the vessels in the compensated reconstructions compared to the initial reconstructions. At the time of writing, our algorithm outperforms the leading result of the CAVAREV ranking list. For the clinical datasets, we found an average reduction of motion artefacts by 13 ± 6%. Vessel sharpness was improved by 25 ± 12% on average. (paper)

  9. Residual motion compensation in ECG-gated interventional cardiac vasculature reconstruction

    Science.gov (United States)

    Schwemmer, C.; Rohkohl, C.; Lauritsch, G.; Müller, K.; Hornegger, J.

    2013-06-01

    Three-dimensional reconstruction of cardiac vasculature from angiographic C-arm CT (rotational angiography) data is a major challenge. Motion artefacts corrupt image quality, reducing usability for diagnosis and guidance. Many state-of-the-art approaches depend on retrospective ECG-gating of projection data for image reconstruction. A trade-off has to be made regarding the size of the ECG-gating window. A large temporal window is desirable to avoid undersampling. However, residual motion will occur in a large window, causing motion artefacts. We present an algorithm to correct for residual motion. Our approach is based on a deformable 2D-2D registration between the forward projection of an initial, ECG-gated reconstruction, and the original projection data. The approach is fully automatic and does not require any complex segmentation of vasculature, or landmarks. The estimated motion is compensated for during the backprojection step of a subsequent reconstruction. We evaluated the method using the publicly available CAVAREV platform and on six human clinical datasets. We found a better visibility of structure, reduced motion artefacts, and increased sharpness of the vessels in the compensated reconstructions compared to the initial reconstructions. At the time of writing, our algorithm outperforms the leading result of the CAVAREV ranking list. For the clinical datasets, we found an average reduction of motion artefacts by 13 ± 6%. Vessel sharpness was improved by 25 ± 12% on average.

  10. Evaluation of ECG-gated [(11)C]acetate PET for measuring left ventricular volumes, mass, and myocardial external efficiency.

    Science.gov (United States)

    Hansson, Nils Henrik; Tolbod, Lars; Harms, Johannes; Wiggers, Henrik; Kim, Won Yong; Hansen, Esben; Zaremba, Tomas; Frøkiær, Jørgen; Jakobsen, Steen; Sørensen, Jens

    2016-08-01

    Noninvasive estimation of myocardial external efficiency (MEE) requires measurements of left ventricular (LV) oxygen consumption with [(11)C]acetate PET in addition to LV stroke volume and mass with cardiovascular magnetic resonance (CMR). Measuring LV geometry directly from ECG-gated [(11)C]acetate PET might enable MEE evaluation from a single PET scan. Therefore, we sought to establish the accuracy of measuring LV volumes, mass, and MEE directly from ECG-gated [(11)C]acetate PET. Thirty-five subjects with aortic valve stenosis underwent ECG-gated [(11)C]acetate PET and CMR. List mode PET data were rebinned into 16-bin ECG-gated uptake images before measuring LV volumes and mass using commercial software and compared to CMR. Dynamic datasets were used for calculation of mean LV oxygen consumption and MEE. LV mass, volumes, and ejection fraction measured by CMR and PET correlated strongly (r = 0.86-0.92, P PET (P PET-based MEE, corrected for bias, correlated fairly with PET/CMR-based MEE (r = 0.60, P PET-based MEE bias was strongly associated with LV wall thickness. Although analysis-related improvements in accuracy are recommended, LV geometry estimated from ECG-gated [(11)C]acetate PET correlate excellently with CMR and can indeed be used to evaluate MEE.

  11. The effect of relaxing music on heart rate and heart rate variability during ECG GATED-myocardial perfusion scintigraphy.

    Science.gov (United States)

    Tan, Yusuf Ziya; Ozdemir, Semra; Temiz, Ahmet; Celik, Fatmanur

    2015-05-01

    The positive changes in human behavior caused by relaxing music demonstrate the psychological effect of music on human body. A meta-analytical study has shown that relaxing music affects blood pressure and heart rate in coronary heart patients and cancer patients. The aim of our study is to research whether there is a significant effect on heart rate and heart rate variability due to listening to relaxing music during ECG GATED MPS imaging under gamma camera. The music group (n = 50 patients) could choose from 15 different musical types including folk music (no lyric). The other 50 patients were placed in a "no music group" and did not get headphones or any music. There was a statistically significant reduction in the heart rate of patients in the music group compared to those in the control group. Relaxing music provides great benefits to both patient and clinician. There is close relationship between relaxing music and health procedure, can use every area of the health noninvasiv, safe, cheap and is a method don't have side effect. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Prospective and retrospective ECG-gating for CT coronary angiography perform similarly accurate at low heart rates

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul, E-mail: paul.stolzmann@usz.ch [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Goetti, Robert; Baumueller, Stephan [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Plass, Andre; Falk, Volkmar [Clinic for Cardiovascular Surgery, University Hospital Zurich (Switzerland); Scheffel, Hans; Feuchtner, Gudrun; Marincek, Borut [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Alkadhi, Hatem [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland); Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Leschka, Sebastian [Institute of Diagnostic Radiology, University Hospital Zurich, Raemistrasse 100, 8091 Zurich (Switzerland)

    2011-07-15

    Objective: To compare, in patients with suspicion of coronary artery disease (CAD) and low heart rates, image quality, diagnostic performance, and radiation dose values of prospectively and retrospectively electrocardiography (ECG)-gated dual-source computed tomography coronary angiography (CTCA) for the diagnosis of significant coronary stenoses. Materials and methods: Two-hundred consecutive patients with heart rates {<=}70 bpm were retrospectively enrolled; 100 patients undergoing prospectively ECG-gated CTCA (group 1) and 100 patients undergoing retrospectively-gated CTCA (group 2). Coronary artery segments were assessed for image quality and significant luminal diameter narrowing. Sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and accuracy of both CTCA groups were determined using conventional catheter angiography (CCA) as reference standard. Radiation dose values were calculated. Results: Both groups were comparable regarding gender, body weight, cardiovascular risk profile, severity of CAD, mean heart rate, heart rate variability, and Agatston score (all p > 0.05). There was no significant difference in the rate of non-assessable coronary segments between group 1 (1.6%, 24/1404) and group 2 (1.4%, 19/1385; p = 0.77); non-diagnostic image quality was significantly (p < 0.001) more often attributed to stair step artifacts in group 1. Segment-based sensitivity, specificity, PPV, NPV, and accuracy were 98%, 98%, 88%, 100%, and 100% among group 1; 96%, 99%, 90%, 100%, and 98% among group 2, respectively. Parameters of diagnostic performance were similar (all p > 0.05). Mean effective radiation dose of prospectively ECG-gated CTCA (2.2 {+-} 0.4 mSv) was significantly (p < 0.0001) smaller than that of retrospectively ECG-gated CTCA (8.1 {+-} 0.6 mSv). Conclusion: Prospectively ECG-gated CTCA yields similar image quality, performs as accurately as retrospectively ECG-gated CTCA in patients having heart rates {<=}70 bpm

  13. Comparative study of image quality and radiation dose between prospective and retrospective ECG gating technique in coronary artery imaging with 64-slice spiral CT

    International Nuclear Information System (INIS)

    Liu Jianxin; Liu Jian; Dou Yanbin; Wang Jichen; Sun Hongyue

    2009-01-01

    Objective: To compare the image quality and radiation dose between prospective ECG-trigering and retrospective ECG gating technique in coronary artery imaging. Methods: 33 patients suspected coronary artery disease were included in this study and divided into experimental group (prospective ECG-triggering coronary artery imaging, heart rate 0.05). The mean DLP of experimental group (234.4 mGy · cm) was DLP of control group (974.4 mGy · cm) 24.1%. The mean effective dose of prospective ECG gating coronary artery imaging was 3.2 mSv. Effective dose reduced 76.47 %. Conclusions: Prospective ECG gating coronary artery imaging can obtain the similar image quality compared with prospective ECG gating coronary artery imaging but the effective dose reduced 76.47 %. Prospective ECG gating coronary artery imaging has clinical value to peoples who are able to not accept high radiation dose and with low heart rate. (authors)

  14. Phase analysis in gated blood pool tomography

    International Nuclear Information System (INIS)

    Nakajima, Kenichi; Bunko, Hisashi; Tada, Akira; Taki, Junichi; Nanbu, Ichiro

    1984-01-01

    Phase analysis of gated blood pool study has been applied to detect the site of accessory conduction pathway (ACP) in the Wolff-Parkinson-White (WPW) syndrome; however, there was a limitation to detect the precise location of ACP by phase analysis alone. In this study, we applied phase analysis to gated blood pool tomography using seven pin hole tomography (7PT) and gated emission computed tomography (GECT) in 21 patients with WPW syndrome and 3 normal subjects. In 17 patients, the sites of ACPs were confirmed by epicardial mapping and the result of the surgical division of ACP. In 7PT, the site of ACP grossly agreed to the abnormal initial phase in phase image in 5 out of 6 patients with left cardiac type. In GECT, phase images were generated in short axial, vertical and horizontal long axial sections. In 8 out of 9 patients, the site of ACP was correctly identified by phase images, and in a patient who had two ACPs, initial phase corresponded to one of the two locations. Phase analysis of gated blood pool tomography has advantages for avoiding overlap of blood pools and for estimating three-dimensional propagation of the contraction, and can be a good adjunctive method in patients with WPW syndrome. (author)

  15. An evaluation of the ECG gated cardiac CT on old myocardial infarction

    International Nuclear Information System (INIS)

    Tanegashima, Kazuhiro; Tejima, Yasuaki; Nakasone, Noriyo; Hyodo, Haruo

    1984-01-01

    In order to examine the accuracy of ECG gated cardiac CT (G-CCT), G-CCT findings were compared with ECG and cardiac echographic findings in 25 cases of old myocardial infarction. From the detection rate according to the infarct area, abnormal findings in the anterior wall and the septum obtained from G-CCT were in good accordance with those from ECG. Although all of the G-CCT findings did not agree with those of cardiac echography in cases in which abnormal findings were seen in multiple areas, the detection rate of cardiac abnormal findings as a whole by G-CCT was the same as that by cardiac echography. (Namekawa K.)

  16. ECG-gated interventional cardiac reconstruction for non-periodic motion.

    Science.gov (United States)

    Rohkohl, Christopher; Lauritsch, Günter; Biller, Lisa; Hornegger, Joachim

    2010-01-01

    The 3-D reconstruction of cardiac vasculature using C-arm CT is an active and challenging field of research. In interventional environments patients often do have arrhythmic heart signals or cannot hold breath during the complete data acquisition. This important group of patients cannot be reconstructed with current approaches that do strongly depend on a high degree of cardiac motion periodicity for working properly. In a last year's MICCAI contribution a first algorithm was presented that is able to estimate non-periodic 4-D motion patterns. However, to some degree that algorithm still depends on periodicity, as it requires a prior image which is obtained using a simple ECG-gated reconstruction. In this work we aim to provide a solution to this problem by developing a motion compensated ECG-gating algorithm. It is built upon a 4-D time-continuous affine motion model which is capable of compactly describing highly non-periodic motion patterns. A stochastic optimization scheme is derived which minimizes the error between the measured projection data and the forward projection of the motion compensated reconstruction. For evaluation, the algorithm is applied to 5 datasets of the left coronary arteries of patients that have ignored the breath hold command and/or had arrhythmic heart signals during the data acquisition. By applying the developed algorithm the average visibility of the vessel segments could be increased by 27%. The results show that the proposed algorithm provides excellent reconstruction quality in cases where classical approaches fail. The algorithm is highly parallelizable and a clinically feasible runtime of under 4 minutes is achieved using modern graphics card hardware.

  17. Automated Agatston score computation in non-ECG gated CT scans using deep learning

    Science.gov (United States)

    Cano-Espinosa, Carlos; González, Germán.; Washko, George R.; Cazorla, Miguel; San José Estépar, Raúl

    2018-03-01

    Introduction: The Agatston score is a well-established metric of cardiovascular disease related to clinical outcomes. It is computed from CT scans by a) measuring the volume and intensity of the atherosclerotic plaques and b) aggregating such information in an index. Objective: To generate a convolutional neural network that inputs a non-contrast chest CT scan and outputs the Agatston score associated with it directly, without a prior segmentation of Coronary Artery Calcifications (CAC). Materials and methods: We use a database of 5973 non-contrast non-ECG gated chest CT scans where the Agatston score has been manually computed. The heart of each scan is cropped automatically using an object detector. The database is split in 4973 cases for training and 1000 for testing. We train a 3D deep convolutional neural network to regress the Agatston score directly from the extracted hearts. Results: The proposed method yields a Pearson correlation coefficient of r = 0.93; p <= 0.0001 against manual reference standard in the 1000 test cases. It further stratifies correctly 72.6% of the cases with respect to standard risk groups. This compares to more complex state-of-the-art methods based on prior segmentations of the CACs, which achieve r = 0.94 in ECG-gated pulmonary CT. Conclusions: A convolutional neural network can regress the Agatston score from the image of the heart directly, without a prior segmentation of the CACs. This is a new and simpler paradigm in the Agatston score computation that yields similar results to the state-of-the-art literature.

  18. Reduction of the estimated radiation dose and associated patient risk with prospective ECG-gated 256-slice CT coronary angiography

    International Nuclear Information System (INIS)

    Efstathopoulos, E P; Kelekis, N L; Pantos, I; Brountzos, E; Argentos, S; Grebac, J; Ziaka, D; Seimenis, I; Katritsis, D G

    2009-01-01

    Computed tomography (CT) coronary angiography has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but high radiation doses have been reported. Prospective ECG-gating using a 'step-and-shoot' axial scanning protocol has been shown to reduce radiation exposure effectively while maintaining diagnostic accuracy. 256-slice scanners with 80 mm detector coverage have been currently introduced into practice, but their impact on radiation exposure has not been adequately studied. The aim of this study was to assess radiation doses associated with CT coronary angiography using a 256-slice CT scanner. Radiation doses were estimated for 25 patients scanned with either prospective or retrospective ECG-gating. Image quality was assessed objectively in terms of mean CT attenuation at selected regions of interest on axial coronary images and subjectively by coronary segment quality scoring. It was found that radiation doses associated with prospective ECG-gating were significantly lower than retrospective ECG-gating (3.2 ± 0.6 mSv versus 13.4 ± 2.7 mSv). Consequently, the radiogenic fatal cancer risk for the patient is much lower with prospective gating (0.0176% versus 0.0737%). No statistically significant differences in image quality were observed between the two scanning protocols for both objective and subjective quality assessments. Therefore, prospective ECG-gating using a 'step-and-shoot' protocol that covers the cardiac anatomy in two axial acquisitions effectively reduces radiation doses in 256-slice CT coronary angiography without compromising image quality.

  19. Gated cardiac blood pool studies in arrhythmias

    International Nuclear Information System (INIS)

    Itti, R.; Casset, D.; Philippe, L.; Cosnay, P.; Fauchier, J.P.

    1988-01-01

    Biventricular phase analysis a gated blood pool studies may help to solve two fundamental questions raised by patients suffering from arrhythmias: localization of an electrical cardiac activation abnormality by means of contraction mapping and assesment of an underlying organic disease using the phase histograms and their standard deviations. Three groups of patients have been evaluated to demonstrate the usefulness of radioisotopic techniques in arrhythmias: 36 patients with a Wolff-Parkinson-White syndrom, 27 patients studied during a ventricular tachycardia attack and 32 patients suspected of arrhythmogenic ventricular dysplasia. Correlations with invasive electrophysiologic studies are presented and the diagnostic and therapeutic implications of these results are discussed [fr

  20. Gated cardiac blood pool studies in arrhythmias

    Energy Technology Data Exchange (ETDEWEB)

    Itti, R.; Casset, D.; Philippe, L.; Cosnay, P.; Fauchier, J.P.

    1988-01-01

    Biventricular phase analysis a gated blood pool studies may help to solve two fundamental questions raised by patients suffering from arrhythmias: localization of an electrical cardiac activation abnormality by means of contraction mapping and assesment of an underlying organic disease using the phase histograms and their standard deviations. Three groups of patients have been evaluated to demonstrate the usefulness of radioisotopic techniques in arrhythmias: 36 patients with a Wolff-Parkinson-White syndrom, 27 patients studied during a ventricular tachycardia attack and 32 patients suspected of arrhythmogenic ventricular dysplasia. Correlations with invasive electrophysiologic studies are presented and the diagnostic and therapeutic implications of these results are discussed.

  1. Diagnosis of accessory conduction pathway using ECG-gated emission CT analysis

    International Nuclear Information System (INIS)

    Misaki, Takuro; Mukai, Keiichi; Tsubota, Makoto; Iwa, Takashi; Nakajima, Ken-ichi; Hisada, Kin-ichi

    1987-01-01

    Pinpointing the location of accessory conduction pathway (ACP) is of great importance in the surgical treatment for Wolff-Parkinson-White (WPW) syndrome. For this purpose, this study explored the usefulness of ECG-gated emission computed tomography (Gated-ECT) in 30 patients who preoperatively underwent Gated-ECT. The site of earliest contraction at level of atrioventicular valves, obtained on tomographic phase analysis, was compared with the site of earliest activation, obtained on epicardial mapping during surgery. The concordance rate of the two methods was 94 % (28/30). Among them, one patient was found to have the association of corrected transposition of great arteries on Gated-ECT. Gated-ECT was, however, of limited value in differentiating right posterior ACP from right postseptal ACP. The discordance between the sites of earliest contraction and activation, which was observed in the two others, was likely due to decreased wall motion resulting from myocardial disturbance. Gated-ECT may have a diagnostic potential for the location of ACP, especially in view of providing images that corresponded to the surgical anatomy. (Namekawa, K.)

  2. The usefulness of treatment evaluation of severe heart failure by ECG-gated myocardial SPECT

    International Nuclear Information System (INIS)

    Ohkoshi, Nobuyuki; Watanabe, Shingo; Matsumoto, Tooru

    2011-01-01

    Our purpose of study was to investigate the usefulness of treatment evaluation of severe heart failure by Electrocardiogram (ECG)-gated myocardial single photon emission computed tomography (SPECT). We evaluated the cardiac function in the case of severe heart failure by gated SPECT and compared it with the cardiac function obtained by left ventriculography (LVG), echocardiography, cardiac MRI, and B-type natriuretic peptide (BNP) values. We investigated the correlation of ejection fraction (EF), time lag of wall motion between the septal and lateral walls of the left ventricle for cardiac resynchronization therapy (CRT) and wall thickening (WT). We classified the left ventricular (LV) into basal, middle and apical areas for comparison of WT. We investigated the effect of a perfusion defect score in these comparisons. The gated SPECT results were correlated with comparative subjects in EF. The results were correlated with MRI on the middle area of the LV in the comparison of WT. We thought it was possible that there was an effect from a perfusion defect score in a time lag comparison of wall motion. Treatment evaluation of severe heart failure by gated SPECT is useful, because it is able to obtain three-dimensional cardiac function analysis, and it offers objectivity and reproducible quantitative evaluation. At the same time, perfusion SPECT is helpful for CRT and LV-plasty. (author)

  3. Assessment of left ventricular performance by ECG-gated SPECT. Comparison with magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tadamura, Eiji; Inubushi, Masayuki; Kubo, Shigeto; Matsumoto, Keiichi; Yokoyama, Hiroshi; Fujita, Toru; Konishi, Junji [Kyoto Univ. (Japan). Faculty of Medicine

    1999-10-01

    In the measurement of a left ventricular volume, MIBI-QGS was compared with MRI. Because it became clear by the experiment using phantom that a volume calculated with QGS was smaller than the actual volume, data of clinical study were corrected. Subjects were 20 patients with coronary artery disease. Fourteen patients had anamnesis of myocardial infarct. ECG-gated SPECT was performed one hour after intravenous injection of MIBI (600 MBq) in rest. End diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) were calculated using QGS. Cine-MR image was obtained by using MR system of 1.5 Tesla within 1 week after SPECT. A condition was as follows; segmented k-space gradient echo with view sharing, TR=11 ms, TE=1.4 ms, flip angle 20 degree, field of view 32 cm, matrix 256 x 196, 8 lines per segment. LVEF, ESV and EF were analysed by Bland-Altman method, and the difference between MIBI-gated-SPECT and MRI was no problem. Horizontal dislocation image and vertical major axis dislocation image were provided. Minor axis crossing images of 10-12 slice were also filmed in order to cover all left ventricles. As a result, availability of MIBI-QGS became clear. Some factors which produces the measurement error are examined. (K.H.)

  4. Ventricular short-axis measurements in patients with pulmonary embolism: Effect of ECG-gating on variability, accuracy, and risk prediction

    International Nuclear Information System (INIS)

    Scheffel, Hans; Stolzmann, Paul; Leschka, Sebastian; Desbiolles, Lotus; Seifert, Burkhardt; Marincek, Borut; Alkadhi, Hatem

    2012-01-01

    Objective: To assess prospectively the intra- and interobserver variability, accuracy, and prognostic value of right and left ventricular short-axis diameter (RVd and LVd) measurements for risk stratification in patients with pulmonary embolism (PE) using ECG-gated compared to non-gated CT. Materials and methods: Sixty consecutive patients (33 women; mean age 58.7 ± 10.3 years) with suspicion of PE underwent both non-gated and ECG-gated chest CT. RVd and LVd on four-chamber views and intra- and interobserver agreements were calculated for both protocols. RVd/LVd ratios were calculated and were related to 30-days adverse clinical events using receiver operating characteristics with area-under-the-curve (AUC) analyses. Results: Both inter- and intraobserver variability showed narrower limits of agreement for all measurements with ECG-gated as compared to non-gated CT. Diameter measurements were significantly lower using non-ECG-gated CT as compared to ECG-gated CT for RVd and LVd (both p < .05). The AUC for the RVd/LVd ratio from ECG-gated CT was significantly larger than that from non-gated CT (0.956, 95% CI: 0.768–0.999 versus 0.675, 95% CI: 0.439–0.860; p = .048). Conclusion: RVd and LVd measurements from ECG-gated chest CT show less intra- and interobserver variability and more accurately reflect ventricular function. In our patient cohort ECG-gated chest CT allows better prediction of short-term outcome of patients with acute PE that needs to be validated in a larger outcome study

  5. Low flip angle spin-echo MR imaging to obtain better Gd-DTPA enhanced imaging with ECG gating

    International Nuclear Information System (INIS)

    Sugimura, Kazuro; Kawamitsu, Hideaki; Yoshikawa, Kazuaki; Kasai, Toshifumi; Yuasa, Koji; Ishida, Tetsuya

    1992-01-01

    ECG-gated spin-echo imaging (ECG-SE) can reduce physiological motion artifact. However, ECG-SE does not provide strong T1-weighted images because repetition time (TR) depends on heart rate (HR). We investigated the usefulness of low flip angle spin-echo imaging (LFSE) in obtaining more T1-dependent contrast with ECG gating. In computer simulation, the predicted image contrast and single-to-noise ratio (SNR) obtained for each flip angle (0-180deg) and each TR (300 msec-1200 msec) were compared with those obtained by conventional T1-weighted spin-echo imaging (CSE: TR=500 msec, TE=20 msec). In clinical evaluation, tissue contrast [contrast index (CI): (SI of lesion-SI of muslce) 2* 100/SI of muscle] obtained by CSE and LFSE were compared in 17 patients. At a TR of 1,000 msec, T1-dependent contrast increased with decreasing flip angle and that at 38deg was identical to that with T1-weighted spin-echo. SNR increased with the flip angle until 100deg, and that at 53deg was identical to that with T1-weighted spin-echo. CI on LFSE (74.0±52.0) was significantly higher than CI on CSE (40.9±35.9). ECG-gated LFSE imaging provides better T1-dependent contrast than conventional ECG-SE. This method was especially useful for Gd-DTPA enhanced MR imaging. (author)

  6. Meta-analysis: diagnostic accuracy of coronary CT angiography with prospective ECG gating based on step-and-shoot, Flash and volume modes for detection of coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Linfeng; Zhou, Tao; Zhang, Ruijie; Peng, Zhaohui; Ding, Juan; Wang, Sen; Li, Min; Sun, Gang [Jinan Military General Hospital, Department of Medical Imaging, Jinan, Shandong Province (China); Xu, Lin [Jinan Military General Hospital, Department of Medical Cardiology, Jinan, Shandong Province (China)

    2014-10-15

    To investigate the diagnostic performance of coronary computed tomographic angiography (CCTA) with prospective electrocardiograph (ECG) gating based on step-and-shoot (SAS), Flash and volume imaging modes. We searched the electronic databases PubMed for all published studies regarding CCTA. We used an exact binomial rendition of the bivariate mixed-effects regression model developed for synthesis of diagnostic data. A total of 21,852 segments, 4,851 vessels and 1,375 patients were identified using database searches. Patient-level pooled sensitivity was 0.99 (95 % confidence interval [CI], 0.98-1.00); specificity was 0.88 (CI, 0.85-0.91). The results showed that the sensitivity and specificity for detection of significant stenosis did not differ in the three protocols (P = 0.24). No heterogeneity was found at the patient level for sensitivity (Q = 26.23; P = 0.12; I {sup 2} = 27.56 % [CI, 0.00-67.02 %]) and specificity (Q = 19.54; P = 0.42; I {sup 2} = 2.78 % [CI, 0.00-66.26 %]). CCTA with prospective ECG gating has similar high diagnostic value to rule out CAD in all three presented modes. (orig.)

  7. An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET

    International Nuclear Information System (INIS)

    Koivumäki, Tuomas; Nekolla, Stephan G; Fürst, Sebastian; Loher, Simone; Schwaiger, Markus; Vauhkonen, Marko; Hakulinen, Mikko A

    2014-01-01

    Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6  ±  3.3 mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4 ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3  ±  1.3 mm) compared to cardiac-gated images (11.3  ±  1.3 mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes. (paper)

  8. Coronary Artery Stent Evaluation Using a Vascular Model at 64-Detector Row CT: Comparison between Prospective and Retrospective ECG-Gated Axial Scans

    International Nuclear Information System (INIS)

    Suzuki, Shigeru; Furui, Shigeru; Kaminaga, Tatsuro; Miyazawa, Akiyoshi; Ueno, Yasunari; Konno, Kumiko; Kuwahara, Sadatoshi; Mehta, Dhruv

    2009-01-01

    We wanted to evaluate the performance of prospective electrocardiogram (ECG)-gated axial scans for assessing coronary stents as compared with retrospective ECG-gated helical scans. As for a vascular model of the coronary artery, a tube of approximately 2.5-mm inner diameter was adopted and as for stents, three (Bx-Velocity, Express2, and Micro Driver) different kinds of stents were inserted into the tube. Both patent and stenotic models of coronary artery were made by instillating different attenuation (396 vs. 79 Hounsfield unit [HU]) of contrast medium within the tube in tube model. The models were scanned with two types of scan methods with a simulated ECG of 60 beats per minute and using display field of views (FOVs) of 9 and 18 cm. We evaluated the in-stent stenosis visually, and we measured the attenuation values and the diameter of the patent stent lumen. The visualization of the stent lumen of the vascular models was improved with using the prospective ECG-gated axial scans and a 9-cm FOV. The inner diameters of the vascular models were underestimated with mean measurement errors of -1.10 to -1.36 mm. The measurement errors were smaller with using the prospective ECG-gated axial scans (Bx-Velocity and Express2, p < 0.0001; Micro Driver, p = 0.0004) and a 9-cm FOV (all stents: p < 0.0001), as compared with the other conditions, respectively. The luminal attenuation value was overestimated in each condition. For the luminal attenuation measurement, the use of prospective ECG-gated axial scans provided less measurement error compared with the retrospective ECG-gated helical scans (all stents: p < 0.0001), and the use of a 9-cm FOV tended to decrease the measurement error. The visualization of coronary stents is improved by the use of prospective ECG-gated axial scans and using a small FOV with reduced blooming artifacts and increased spatial resolution

  9. Hybrid ECG-gated versus non-gated 512-slice CT angiography of the aorta and coronary artery: image quality and effect of a motion correction algorithm.

    Science.gov (United States)

    Lee, Ji Won; Kim, Chang Won; Lee, Geewon; Lee, Han Cheol; Kim, Sang-Pil; Choi, Bum Sung; Jeong, Yeon Joo

    2018-02-01

    Background Using the hybrid electrocardiogram (ECG)-gated computed tomography (CT) technique, assessment of entire aorta, coronary arteries, and aortic valve can be possible using single-bolus contrast administration within a single acquisition. Purpose To compare the image quality of hybrid ECG-gated and non-gated CT angiography of the aorta and evaluate the effect of a motion correction algorithm (MCA) on coronary artery image quality in a hybrid ECG-gated aorta CT group. Material and Methods In total, 104 patients (76 men; mean age = 65.8 years) prospectively randomized into two groups (Group 1 = hybrid ECG-gated CT; Group 2 = non-gated CT) underwent wide-detector array aorta CT. Image quality, assessed using a four-point scale, was compared between the groups. Coronary artery image quality was compared between the conventional reconstruction and motion correction reconstruction subgroups in Group 1. Results Group 1 showed significant advantages over Group 2 in aortic wall, cardiac chamber, aortic valve, coronary ostia, and main coronary arteries image quality (all P ECG-gated CT significantly improved the heart and aortic wall image quality and the MCA can further improve the image quality and interpretability of coronary arteries.

  10. Estimation of the radiation exposure of a chest pain protocol with ECG-gating in dual-source computed tomography

    International Nuclear Information System (INIS)

    Ketelsen, Dominik; Luetkhoff, Marie H.; Thomas, Christoph; Werner, Matthias; Tsiflikas, Ilias; Reimann, Anja; Kopp, Andreas F.; Claussen, Claus D.; Heuschmid, Martin; Buchgeister, Markus; Burgstahler, Christof

    2009-01-01

    The aim of the study was to evaluate radiation exposure of a chest pain protocol with ECG-gated dual-source computed tomography (DSCT). An Alderson Rando phantom equipped with thermoluminescent dosimeters was used for dose measurements. Exposure was performed on a dual-source computed tomography system with a standard protocol for chest pain evaluation (120 kV, 320 mAs/rot) with different simulated heart rates (HRs). The dose of a standard chest CT examination (120 kV, 160 mAs) was also measured. Effective dose of the chest pain protocol was 19.3/21.9 mSv (male/female, HR 60), 17.9/20.4 mSv (male/female, HR 80) and 14.7/16.7 mSv (male/female, HR 100). Effective dose of a standard chest examination was 6.3 mSv (males) and 7.2 mSv (females). Radiation dose of the chest pain protocol increases significantly with a lower heart rate for both males (p = 0.040) and females (p = 0.044). The average radiation dose of a standard chest CT examination is about 36.5% that of a CT examination performed for chest pain. Using DSCT, the evaluated chest pain protocol revealed a higher radiation exposure compared with standard chest CT. Furthermore, HRs markedly influenced the dose exposure when using the ECG-gated chest pain protocol. (orig.)

  11. Design and development of a new pulsating cardiac coronary phantom for ECG-gated CT and its experimental characteristics

    International Nuclear Information System (INIS)

    Shen, Yun; Sato, Munekuni; Kimura, Fumiko; Jinzaki, Masahiro; Kuribayashi, Sachio; Horiguchi, Jun; Ito, Katsuhide

    2005-01-01

    The optimal pulsating cardiac phantom is an important tool for the evaluation of cardiac images and cardiac applications on electrocardiogram (ECG)-gated multidetector-row CT (MDCT). The purpose of this study was to demonstrate the design and fabrication of the pulsating cardiac coronary phantom. The newly developed pulsating cardiac coronary phantom has the following five key advantages: a driver component that uses only one servomotor to move the phantom in three dimensions (X, Y, and Z directions) with 16 presets of different heart types (heartbeat: 0-120 bpm; ejection fraction: 0-90%); versatile pumping and filling phases to simulate a real heart in a cardiac cycle can be incorporated into the driver sequence including shift of patient heartbeat or irregular pulse (maximum: 200 different heart waves in one scan); a cardiac coronary component constituted of an acrylic/silicon/rubber tube (2-6 mm inner diameter) with stent/in-stent restenosis/stenosis/soft plaque/calcification parts and maximum 16 coronary arteries that can be attached to the phantom in the same scan; the complete phantom can be submerged in a tank to simulate the heart and its surrounding tissues; ECG gating can be from interior trigger and exterior trigger. It has been confirmed that the developed pulsating cardiac phantom is very useful to quantitatively assess imaging of the heart and coronary arteries during phantom experiments. (author)

  12. Imaging quality and effective radiation dose of prospective ECG-gated axial multidetector row computed tomography coronary angiography

    International Nuclear Information System (INIS)

    Capunay, C.; Carrascosa, P.; Vallejos, J.; Deviggiano, A.; Pollono, P.M.; Garcia, M.J.

    2011-01-01

    Objective. To determine the imaging quality and effective radiation dose (ERD) of prospective ECG-gated multidetector row computed tomography coronary angiography (PMDCTCA) compared to retrospective ECG-gating (RMDCT-CA). Materials and Methods. Forty-five PMDCT-CA scans were retrospectively reviewed for assessing imaging quality and ERD, and compared to 90 RMDCT-CA scans performed with (n=45) and without (n=45) tube current modulation, selected from our database on the basis of similar demographical characteristics. ERD was compared between all three groups. Imaging quality was assessed by two independent observers and compared to the imaging quality of the group of RMDCT-CA scans performed with tube current modulation. The interobserver variability was also determined. Results. There were no significant differences in imaging quality between the two groups. Interobserver variability was k=0.92 (95 % CI: 0.87-0.96). The ERD (mean ± SD) using PMDCT-CA was 2.88 ± 0.37 mSv compared to 10.50 ± 1.15 mSv (p [es

  13. Equilibrium blood pool scanning in the evaluation of hemophilic arthropathy

    International Nuclear Information System (INIS)

    Spies, S.; Green, D.; Rana, N.A.; Milgram, J.W.; Mintzer, R.

    1978-01-01

    Arthropathy was evaluated in six patients with severe hemophilia (factor VIII<1%) using the technique of blood pool scanning. Employing an in vivo method for erythrocyte labelling with technetium-99m, a dynamic perfusion sequence was obtained using a scintillation camera over the joint(s) to be examined. Subsequently, equilibrium blood pool images of the joints were obtained to determine regional blood volume. In young patients with repeated episodes of acute hemarthrosis, increased vascularity and increased blood pool in the affected joints were demonstrated. In older patients with fixed, contracted joints and degenerative arthropathy, vascularity and regional blood volume were not abnormal. Blood pool scanning is a safe, non-invasive technique that augments the clinical and radiographic examination of the joints. The method is helpful in distinguishing acute joint bleeding from chronic synovitis and arthritis, and may prove useful in selecting patients for synovectomy. (author)

  14. The evaluation of viability in infarcted myocardium using gated blood pool scintigraphy during combined infusion of isosorbide dinitrate and dobutamine infusion

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Yasushi; Sugihara, Hiroki; Nakagawa, Tatsuya (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1990-02-01

    Nineteen patients with acute or old myocardial infarction underwent ECG-gated blood pool scintigraphy after iv injection of isosorbide dinitrate (ISDN) and combined ISDN and dobutamine (D) (ISDN+D), with the purpose of evaluating wall motion abnormality, as well as hemodynamic parameters. Heart rate increased after iv injection of both ISDN and ISDN+D. Although diastolic and systolic blood pressures decreased with ISDN, they increased with ISDN+D. Left ventricular ejection fraction (EF) increased by iv injection of ISDN+D. Both end-diastolic and end-systolic volumes decreased with ISDN and ISDN+D. A decreased stroke volume was also associated with iv injection of ISDN. Wall motion abnormality in the infarcted myocardium was graded on a 1-5 score: 1-dyskinesis, 2-akinesis, 3-severe hypokinesis, 4-mild hypokinesis, and 5-normal. Improvement was observed in 43% for dyskinesis after iv injection of both ISDN and ISDN+D; in 54% and 65%, with ISDN and ISDN+D respectively, for akinesis and 53% and 77% for severe hypokinesis. In comparing wall motion score with relative Tl uptake (RTU) on exercise Tl-201 scintigraphy, the correlation between wall motion score and RTU on the 3-hr image was higher after iv injection of ISDN+D (r=0.66) than after iv injection of ISDN (r=0.57). Although a significantly improved regional EF after iv injection of ISDN+D was associated with redistributed segments on the 3-hr image, regional EF was sometimes improved even in the non-redistributed segments on the 3-hr image. (N.K.).

  15. Assessment of the effect of revascularization early after CABG using ECG-gated perfusion single-photon emission tomography

    International Nuclear Information System (INIS)

    Kubo, Shigeto; Tadamura, Eiji; Kudoh, Takashi; Inubushi, Masayuki; Konishi, Junji; Ikeda, Tadashi; Koshiji, Takaaki; Nishimura, Kazunobu; Komeda, Masashi; Tamaki, Nagara

    2001-01-01

    When an arterial graft is used, reversible perfusion defects on single-photon emission tomography (SPET) perfusion images are occasionally observed early after coronary artery bypass graft surgery (CABG), owing to the restricted flow capacity. The purpose of this study was to determine whether the functional information obtained with electrocardiography (ECG)-gated perfusion SPET could be helpful in evaluating the effect of revascularization early after CABG. Twenty-three patients (18 men and 5 women, mean age 65±9 years) underwent stress/re-injection thallium-201 ECG-gated SPET before and 4 weeks after CABG (13 with exercise and 10 with dipyridamole). Patency of all grafts was confirmed by coronary angiography 1 month after CABG. Cardiac functional data including the left ventricular ejection fraction (LVEF) and the transient ischaemic dilatation (TID) ratio were analysed using a commercially available automated program. The conventional stress and re-injection tomograms were interpreted by means of a five-point scoring system in a nine-segment model. Stress-induced reversible 201 Tl perfusion defects were present in 64% of the myocardial segments bypassed by patent arterial grafts, in contrast to 42% of the myocardial segments bypassed by patent venous grafts (χ 2 =7.8, P=0.005). Of the 23 patients, 12 showed improvement in summed ischaemic scores (group 1), while 11 had no change or deterioration (group 2), although all grafts were patent on postoperative catheterization. The TID ratio improved in both group 1 and group 2 before and after CABG (1.14±0.13 vs 0.99±0.07, P=0.001 and 1.09±0.07 vs 0.94±0.05, P=0.002, respectively). However, LVEF did not significantly improve in group 1 or group 2 after CABG (42.5%±9.9% vs 47.5%±11.8%, and 52.1%±7.5% vs 53.1%±5.9%, respectively). Perfusion imaging or LVEF assessment is of limited value early after CABG. The TID ratio obtained with ECG-gated perfusion SPET may be a useful marker to evaluate the effect of

  16. Noninvasive coronary artery imaging by multislice spiral computed tomography. A novel approach for a retrospectively ECG-gated reconstruction technique

    International Nuclear Information System (INIS)

    Sato, Yuichi; Kanmatsuse, Katsuo; Inoue Fumio

    2003-01-01

    Although the excellent spatial resolution of multislice spiral computed tomography (MSCT) enables the coronary arteries to be visualized, its limited temporal resolution results in poor image reproducibility because of cardiac motion artifact (CMA) and hence limits its widespread clinical use. A novel retrospectively electrocardiogram (ECG)-gated reconstruction method has been developed to minimize CMA. In 88 consecutive patients, the scan data were reconstructed using 2 retrospectively ECG-gated reconstruction methods. Method 1: the end of the reconstruction window (250 ms) was positioned at the peak of the P wave on ECG, which corresponded to the end of the slow filling phase during diastole immediately before atrial contraction. Method 2 (conventional method): relative retrospective gating with 50% referred to the R-R interval was performed so that the beginning of the reconstruction window (250 ms) was positioned at the halfway point between the R-R intervals of the heart cycle. The quality of the coronary artery images was evaluated according to the presence or absence of CMA. The assessment was applied to the left main coronary artery (LMCA), the left anterior descending artery (LAD, segments no.6, no.7, and no.8), the left circumflex artery (LCx, segments no.11 and no.13) and the right coronary artery (RCA, segments no.1, no.2 and no.3). The first diagonal artery (no.9-1), the obtuse marginal artery (no.12-1), the posterior descending artery (no.4-PD), the atrioventricular node branch (no.4-AV) and the first right ventricular branch (RV) were also evaluated. Of the 88 patients, 85 were eligible for image evaluation. Method 1 allowed visualization of the major coronary arteries without CMA in the majority of patients. The left coronary artery (LCA) system (segments no.5-7, no.11 and no.13) and the proximal portion of the RCA were visualized in more than 94% of patients. Artifact-free visualization of the distal portion of the LAD (segment no.8) and RCA (no.4

  17. Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients

    International Nuclear Information System (INIS)

    Salem, Randa; Remy-Jardin, Martine; Delhaye, Damien; Khalil, Chadi; Teisseire, Antoine; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

    2006-01-01

    The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without β-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., ''morphologic scans'') and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., ''functional scans''). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11±2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n=4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n=6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% (±9.5; range: 20-72) and the mean LVEF was 58.23% (±10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end-diastolic ventricular volumes. The mean (±SD) DLP

  18. Evaluation of left ventricular ejection fraction from radial long-axis tomography. A new reconstruction algorithm for ECG-gated technetium-99m Sestamibi SPECT

    International Nuclear Information System (INIS)

    Tsujimura, Eiichiro; Kusuoka, Hideo; Uehara, Toshiisa

    1997-01-01

    Radial long-axis tomography can provide views similar to contrast left ventriculography (LVG) including the basal and apical areas of the left ventricle, not possible in routine short-axis tomography. We applied this method to ECG-gated Tc-99m Sestamibi (MIBI) myocardial SPECT images to estimate the left ventricular ejection fraction (LVEF). ECG-gated Tc-99m MIBI SPECT was performed with a temporal resolution of 10 frames per R-R interval. LVEF was calculated on the basis of left ventricular volume estimates at end diastole (ED) and end systole (ES) with using an ellipsoid body model. To validate this method, LVEF's derived from ECG-gated Tc-99m MIBI SPECT were compared with those from LVG in 11 patients with coronary artery disease. There was a close linear correlation between LVEF values calculated from Tc-99m MIBI SPECT and those from LVG (r=0.89, p<0.001), although the gated SPECT underestimated LVEF compared to LVG. The technique showed excellent reproducibility (intra-observer variability, r=0.96, p<0.001; inter-observer variability, r=0.71, p<0.005). The radial long-axis tomography technique gives a good estimate of LVEF, in agreement with estimates based on LVG. ECG-gated Tc-99m MIBI SPECT can, therefore, be applicable to assess myocardial perfusion and ventricular function at the same time. (author)

  19. Evaluation of left ventricular ejection fraction from radial long-axis tomography. A new reconstruction algorithm for ECG-gated technetium-99m Sestamibi SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Tsujimura, Eiichiro; Kusuoka, Hideo; Uehara, Toshiisa [Osaka Univ. (Japan). Faculty of Medicine] [and others

    1997-08-01

    Radial long-axis tomography can provide views similar to contrast left ventriculography (LVG) including the basal and apical areas of the left ventricle, not possible in routine short-axis tomography. We applied this method to ECG-gated Tc-99m Sestamibi (MIBI) myocardial SPECT images to estimate the left ventricular ejection fraction (LVEF). ECG-gated Tc-99m MIBI SPECT was performed with a temporal resolution of 10 frames per R-R interval. LVEF was calculated on the basis of left ventricular volume estimates at end diastole (ED) and end systole (ES) with using an ellipsoid body model. To validate this method, LVEF`s derived from ECG-gated Tc-99m MIBI SPECT were compared with those from LVG in 11 patients with coronary artery disease. There was a close linear correlation between LVEF values calculated from Tc-99m MIBI SPECT and those from LVG (r=0.89, p<0.001), although the gated SPECT underestimated LVEF compared to LVG. The technique showed excellent reproducibility (intra-observer variability, r=0.96, p<0.001; inter-observer variability, r=0.71, p<0.005). The radial long-axis tomography technique gives a good estimate of LVEF, in agreement with estimates based on LVG. ECG-gated Tc-99m MIBI SPECT can, therefore, be applicable to assess myocardial perfusion and ventricular function at the same time. (author)

  20. 128-slice CT angiography of the aorta without ECG-gating: efficacy of faster gantry rotation time and iterative reconstruction in terms of image quality and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Vincenzo; Garattoni, Monica; Buia, Francesco; Attina, Domenico; Lovato, Luigi; Zompatori, Maurizio [University Hospital ' ' S.Orsola' ' , Cardio-Thoracic-Vascular Department, Cardio-Thoracic Radiology Unit, Bologna (Italy)

    2016-02-15

    To evaluate image quality and radiation dose of non ECG-gated 128-slice CT angiography of the aorta (CTAA) with fast gantry rotation time and iterative reconstruction. Four hundred and eighty patients underwent non ECG-gated CTAA. Qualitative and quantitative image quality assessments were performed. Radiation dose was assessed and compared with the dose of patients who underwent ECG-gated CTAA (n = 126) and the dose of previous CTAA performed with another CT (n = 339). Image quality (aortic root-ascending portion) was average-to-excellent in more than 94 % of cases, without any non-diagnostic scan. For proximal coronaries, image quality was average-to-excellent in more than 50 %, with only 21.5 % of non-diagnostic cases. Quantitative analysis results were also good. Mean radiation dose for thoracic CTAA was 5.6 mSv versus 20.6 mSv of ECG-gated protocol and 20.6 mSv of 16-slice CTAA scans, with an average dose reduction of 72.8 % (p < 0.001). Mean radiation dose for thoracic-abdominal CTAA was 9.7 mSv, versus 20.9 mSv of 16-slice CTAA scans, with an average dose reduction of 53.6 % (p < 0.001). Non ECG-gated 128-slice CTAA is feasible and able to provide high quality visualization of the entire aorta without significant motion artefacts, together with a considerable dose and contrast media volume reduction. (orig.)

  1. 128-slice CT angiography of the aorta without ECG-gating: efficacy of faster gantry rotation time and iterative reconstruction in terms of image quality and radiation dose

    International Nuclear Information System (INIS)

    Russo, Vincenzo; Garattoni, Monica; Buia, Francesco; Attina, Domenico; Lovato, Luigi; Zompatori, Maurizio

    2016-01-01

    To evaluate image quality and radiation dose of non ECG-gated 128-slice CT angiography of the aorta (CTAA) with fast gantry rotation time and iterative reconstruction. Four hundred and eighty patients underwent non ECG-gated CTAA. Qualitative and quantitative image quality assessments were performed. Radiation dose was assessed and compared with the dose of patients who underwent ECG-gated CTAA (n = 126) and the dose of previous CTAA performed with another CT (n = 339). Image quality (aortic root-ascending portion) was average-to-excellent in more than 94 % of cases, without any non-diagnostic scan. For proximal coronaries, image quality was average-to-excellent in more than 50 %, with only 21.5 % of non-diagnostic cases. Quantitative analysis results were also good. Mean radiation dose for thoracic CTAA was 5.6 mSv versus 20.6 mSv of ECG-gated protocol and 20.6 mSv of 16-slice CTAA scans, with an average dose reduction of 72.8 % (p < 0.001). Mean radiation dose for thoracic-abdominal CTAA was 9.7 mSv, versus 20.9 mSv of 16-slice CTAA scans, with an average dose reduction of 53.6 % (p < 0.001). Non ECG-gated 128-slice CTAA is feasible and able to provide high quality visualization of the entire aorta without significant motion artefacts, together with a considerable dose and contrast media volume reduction. (orig.)

  2. Pulmonary artery and right ventricle assessment in pulmonary hypertension. Correlation between functional parameters of ECG-gated CT and right-side heart catheterization

    Energy Technology Data Exchange (ETDEWEB)

    Abel, Elodie; Jankowski, Adrien [Clinique univ. de radiologie et imagerie medicale, CHU Grenoble (France); Pison, Christophe [Clinique univ. de pneumologie, CHU Grenoble (France); Bosson, Jean Luc [Dept. of Statistics, CIC, CHU Grenoble (France); Bouvaist, Helene [Clinique univ. de cardiologie, CHU Grenoble (France); Ferretti, Gilbert R. [Clinique univ. de radiologie et imagerie medicale, CHU Grenoble (France); Univ. J. Fourier, Grenoble (France); INSERM U 823, Inst. A. Bonniot, la Tronche (France)], e-mail: gferretti@chu-grenoble.fr

    2012-09-15

    Background: Right ventricular function predicts outcome in patients with pulmonary hypertension (PH). Therefore accurate assessment of right ventricular function is essential to graduate severity, assess follow-up, and response to therapy. Purpose: To evaluate whether PH severity could be assessed using electrocardiography-gated CT (ECG-gated CT) functional parameters. A further objective was to evaluate cardiac output (CO) using two ECG-gated CT methods: the reference Simpson technique and the fully automatic technique generated by commercially available cardiac software. Material and Methods: Our institutional review board approved this study; patient consent was not required. Twenty-seven patients who had undergone ECG-gated CT and right heart catheterization (RHC) were included. Two independent observers measured pulmonary artery (PA) diameter, PA distensibility, aorta diameter, right ventricular cardiac output (CT-RVCO) and right ventricular ejection fraction (CT-RVEF) with automatic and Simpson techniques on ECG-gated CT. RHC-CO and mean pulmonary arterial pressure (mPAP) were measured on RHC. Relationship between ECG-gated CT and RHC measurements was tested with linear regression analysis. Results: Inter-observer agreement was good for all measurements (r > 0.7) except for CT-RVCO calculated with Simpson's technique (r = 0.63). Pulmonary artery (PA) distensibility was significantly correlated to mPAP (r = -0.426, P = 0.027). CT-RVEF was correlated with mPAP only when issued from Simpson technique (r = -0.417, P = 0.034). CT-RVEF was not significantly correlated to RHC-CO (P > 0.2). CT-RVCO measured with Simpson technique (r = 0.487, P = 0.010) and automatic segmentation (r = 0.549, P 0.005) correlated equally with RHC-CO. Conclusion: CT-RVEF and CT-RVCO measured on ECG-gated CT are significantly correlated, respectively, to mPAP and RHC-CO in this population with severe reduction of the right ventricular ejection fraction and could be useful for

  3. Pulmonary artery and right ventricle assessment in pulmonary hypertension. Correlation between functional parameters of ECG-gated CT and right-side heart catheterization

    International Nuclear Information System (INIS)

    Abel, Elodie; Jankowski, Adrien; Pison, Christophe; Bosson, Jean Luc; Bouvaist, Helene; Ferretti, Gilbert R.

    2012-01-01

    Background: Right ventricular function predicts outcome in patients with pulmonary hypertension (PH). Therefore accurate assessment of right ventricular function is essential to graduate severity, assess follow-up, and response to therapy. Purpose: To evaluate whether PH severity could be assessed using electrocardiography-gated CT (ECG-gated CT) functional parameters. A further objective was to evaluate cardiac output (CO) using two ECG-gated CT methods: the reference Simpson technique and the fully automatic technique generated by commercially available cardiac software. Material and Methods: Our institutional review board approved this study; patient consent was not required. Twenty-seven patients who had undergone ECG-gated CT and right heart catheterization (RHC) were included. Two independent observers measured pulmonary artery (PA) diameter, PA distensibility, aorta diameter, right ventricular cardiac output (CT-RVCO) and right ventricular ejection fraction (CT-RVEF) with automatic and Simpson techniques on ECG-gated CT. RHC-CO and mean pulmonary arterial pressure (mPAP) were measured on RHC. Relationship between ECG-gated CT and RHC measurements was tested with linear regression analysis. Results: Inter-observer agreement was good for all measurements (r > 0.7) except for CT-RVCO calculated with Simpson's technique (r = 0.63). Pulmonary artery (PA) distensibility was significantly correlated to mPAP (r = -0.426, P = 0.027). CT-RVEF was correlated with mPAP only when issued from Simpson technique (r = -0.417, P = 0.034). CT-RVEF was not significantly correlated to RHC-CO (P > 0.2). CT-RVCO measured with Simpson technique (r = 0.487, P = 0.010) and automatic segmentation (r = 0.549, P 0.005) correlated equally with RHC-CO. Conclusion: CT-RVEF and CT-RVCO measured on ECG-gated CT are significantly correlated, respectively, to mPAP and RHC-CO in this population with severe reduction of the right ventricular ejection fraction and could be useful for evaluating

  4. Calculation of left ventricular volume and ejection fraction from ECG-gated myocardial SPECT. Automatic detection of endocardial borders by threshold method

    International Nuclear Information System (INIS)

    Fukushi, Shoji; Teraoka, Satomi.

    1997-01-01

    A new method which calculate end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) of the left ventricle from myocardial short axis images of ECG-gated SPECT using 99m Tc myocardial perfusion tracer has been designed. Eight frames per cardiac cycle ECG-gated 180 degrees SPECT was performed. Threshold method was used to detect myocardial borders automatically. The optimal threshold was 45% by myocardial SPECT phantom. To determine if EDV, ESV and LVEF can also be calculated by this method, 12 patients were correlated ventriculography (LVG) for 10 days each. The correlation coefficient with LVG was 0.918 (EDV), 0.935 (ESV) and 0.900 (LVEF). This method is excellent at objectivity and reproductivity because of the automatic detection of myocardial borders. It also provides useful information on heart function in addition to myocardial perfusion. (author)

  5. Visibility of the origin and proximal course of coronary arteries on non-ECG-gated heart CT in patients with congenital heart disease

    International Nuclear Information System (INIS)

    Goo, Hyun Woo; Park, In-Sook; Ko, Jae Kon; Kim, Young Hwee; Seo, Dong-Man; Yun, Tae-Jin; Park, Jeong-Jun

    2005-01-01

    There is little information on the ability of non-ECG-gated cardiac CT to demonstrate the coronary arteries of children. To evaluate the visibility of the origin and proximal course of coronary arteries on non-ECG-gated cardiac CT, in which the coronary artery was not of primary diagnostic concern, in children with congenital heart disease. From December 2002 to March 2004, 126 cardiac CT examinations from 104 children (median age 11 months; age range 1 day to 15 years) were evaluated. All patients had ventriculo-arterial concordance and no malformations of the great arteries; those with coronary artery anomalies were excluded. Contrast-enhanced 16-slice spiral CT was performed without ECG-gating and multiplanar images for coronary arteries were obtained. The visibility of coronary artery origins was graded on a three-point scale, while nine segments of the arteries were graded on a four-point scale. CT images in which it was possible to trace the coronary arteries were considered diagnostic. The visibility of each whole coronary artery and the origins and proximal four segments of coronary arteries were calculated. The visibility of coronary arteries was also correlated with patient age. The percentage of CT images of diagnostic quality was 49.3% for the whole coronary artery and 81.7% for the origins and proximal four segments. There was a significant positive correlation between the visibility of coronary arteries and age. Non-ECG-gated cardiac CT, in which the coronary artery is not of primary diagnostic concern, is frequently able to visualize the origin and proximal course of coronary arteries and may be helpful in detecting coronary artery anomalies in children with congenital heart disease. (orig.)

  6. Assessment of Double Outlet Right Ventricle Associated with Multiple Malformations in Pediatric Patients Using Retrospective ECG-Gated Dual-Source Computed Tomography.

    Directory of Open Access Journals (Sweden)

    Ke Shi

    Full Text Available To evaluate the feasibility and diagnostic accuracy of retrospective electrocardiographically (ECG-gated dual-source computed tomography (DSCT for the assessment of double outlet right ventricle (DORV and associated multiple malformations in pediatric patients.Forty-seven patients <10 years of age with DORV underwent retrospective ECG-gated DSCT. The location of the ventricular septal defect (VSD, alignment of the two great arteries, and associated malformations were assessed. The feasibility of retrospective ECG-gated DSCT in pediatric patients was assessed, the image quality of DSCT and the agreement of the diagnosis of associated malformations between DSCT and transthoracic echocardiography (TTE were evaluated, the diagnostic accuracies of DSCT and TTE were referred to surgical results, and the effective doses were calculated.Apart from DORV, 109 associated malformations were confirmed postoperatively. There was excellent agreement (κ = 0.90 for the diagnosis of associated malformations between DSCT and TTE. However, DSCT was superior to TTE in demonstrating paracardiac anomalies (sensitivity, coronary artery anomalies: 100% vs. 80.00%, anomalies of great vessels: 100% vs. 88.57%, separate thoracic and abdominal anomalies: 100% vs. 76.92%, respectively. Combined with TTE, DSCT can achieve excellent diagnostic performance in intracardiac anomalies (sensitivity, 91.30% vs. 100%. The mean image quality score was 3.70 ± 0.46 (κ = 0.76. The estimated mean effective dose was < 1 mSv (0.88 ± 0.34 mSv.Retrospective ECG-gated DSCT is a better diagnostic tool than TTE for pediatric patients with complex congenital heart disease such as DORV. Combined with TTE, it may reduce or even obviate the use of invasive cardiac catheterization, and thus expose the patients to a much lower radiation dose.

  7. Low dose prospective ECG-gated delayed enhanced dual-source computed tomography in reperfused acute myocardial infarction comparison with cardiac magnetic resonance

    International Nuclear Information System (INIS)

    Wang Rui; Zhang Zhaoqi; Xu Lei; Ma Qin; He Yi; Lu Dongxu; Yu Wei; Fan Zhanming

    2011-01-01

    Purpose: To determine whether prospective electrocardiogram (ECG)-gated delayed contrast-enhanced dual-source computed tomography (DCE-DSCT) can accurately delineate the extension of myocardial infarction (MI) compared with delayed enhanced cardiac MR (DE-MR). Material and methods: Eleven patients were examined using dual-source CT and cardiac MR in 2 weeks after a first reperfused MI. DCE-DSCT scan protocol was performed with prospective ECG-gating sequential scan model 7 min after contrast administration. In a 17-model, infarcted myocardium detected by DE-MR was categorized as transmural and subendocardial extension. Segment of infarcted location and graded transmurality were compared between DCE-MDCT and DE-MR. Results: In all eleven patients, diagnostic quality was obtained for depicting delayed enhanced myocardium. Agreement between DCE-DSCT and MR was good on myocardial segment based comparison (kappa = 0.85, p < 0.001), and on transmural and subendocardial infarction type comparison (kappa = 0.82, p < 0.001, kappa = 0.52, p < 0.001, respectively). CT value was higher on infarcted region than that of normal region (100.02 ± 9.57 HU vs. 72.63 ± 7.32 HU, p < 0.001). Radiation dose of prospectively ECG-gating protocol were 0.99 ± 0.08 mSv (0.82-1.19 mSv). Conclusions: Prospective ECG-gated DCE-DSCT can accurately assess the extension and the patterns of myocardial infarction with low radiation dose.

  8. Prospective ECG triggering versus low-dose retrospective ECG-gated 128-channel CT coronary angiography: comparison of image quality and radiation dose

    International Nuclear Information System (INIS)

    Feng, Q.; Yin, Y.; Hua, X.; Zhu, R.; Hua, J.; Xu, J.

    2010-01-01

    Aim: To evaluate image quality and radiation dose for 128-detector prospective electrocardiogram (ECG)-gated computed tomography coronary angiography (CTCA) compared with a low-dose retrospective ECG-gated imaging protocol. Materials and methods: Thirty-one and 47 patients suspected of having coronary artery disease were enrolled into groups examined using prospective and low-dose retrospective ECG-gated CT protocols respectively. All examinations were performed on a 128-detector CT system (Definition AS, Siemens Healthcare, Forchheim, Germany). Prospective CTCA was performed using following parameters: tube voltage 100 kV; tube current 205 mAs; centre of acquisition window 70% of the RR interval. The tube current for low-dose retrospective ECG-gated CTCA was full dose during 40-70% of the RR interval and partial dose for the rest of RR interval. The pitch varied between 0.2 and 0.5 depending on heart rate and patient size. Image quality of coronary arteries was evaluated using a four-point grading scale. The signal-to-noise ratios (SNRs) of enhanced arteries and myocardium were also measured, corresponding contrast-to-noise ratios (CNRs) were calculated, and the radiation doses received were recorded. Results: There was a significant difference in the image quality scores between the retrospective and prospective gating protocols (Chi-square = 15.331, p = 0.009). There was no significant difference between the SNRs of the contrasted artery and myocardium in these two groups, but the CNRs were increased in the prospective group. The mean radiation dose of prospective gating group was 2.71 ± 0.67 mSv (range, 1.67-3.59 mSv), which was significantly lower than that of the retrospective group (p < 0.001). Conclusion: Prospective CT angiography can achieve lower radiation dose than that of low-dose retrospective CT angiography, with preserved image quality.

  9. Low dose prospective ECG-gated delayed enhanced dual-source computed tomography in reperfused acute myocardial infarction comparison with cardiac magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang Rui, E-mail: rui_wang1979@yahoo.cn [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Zhang Zhaoqi, E-mail: zhaoqi5000@vip.sohu.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Xu Lei, E-mail: leixu2001@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Ma Qin, E-mail: tel1367@gmail.com [Department of Emergency, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); He Yi, E-mail: heyi139@sina.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Lu Dongxu, E-mail: larry.hi@163.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yu Wei, E-mail: yuwei02@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Fan Zhanming, E-mail: fanzm120@tom.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China)

    2011-11-15

    Purpose: To determine whether prospective electrocardiogram (ECG)-gated delayed contrast-enhanced dual-source computed tomography (DCE-DSCT) can accurately delineate the extension of myocardial infarction (MI) compared with delayed enhanced cardiac MR (DE-MR). Material and methods: Eleven patients were examined using dual-source CT and cardiac MR in 2 weeks after a first reperfused MI. DCE-DSCT scan protocol was performed with prospective ECG-gating sequential scan model 7 min after contrast administration. In a 17-model, infarcted myocardium detected by DE-MR was categorized as transmural and subendocardial extension. Segment of infarcted location and graded transmurality were compared between DCE-MDCT and DE-MR. Results: In all eleven patients, diagnostic quality was obtained for depicting delayed enhanced myocardium. Agreement between DCE-DSCT and MR was good on myocardial segment based comparison (kappa = 0.85, p < 0.001), and on transmural and subendocardial infarction type comparison (kappa = 0.82, p < 0.001, kappa = 0.52, p < 0.001, respectively). CT value was higher on infarcted region than that of normal region (100.02 {+-} 9.57 HU vs. 72.63 {+-} 7.32 HU, p < 0.001). Radiation dose of prospectively ECG-gating protocol were 0.99 {+-} 0.08 mSv (0.82-1.19 mSv). Conclusions: Prospective ECG-gated DCE-DSCT can accurately assess the extension and the patterns of myocardial infarction with low radiation dose.

  10. Detection of Airway Anomalies in?Pediatric?Patients with Cardiovascular Anomalies with Low Dose Prospective ECG-Gated Dual-Source CT

    OpenAIRE

    Jiao, Hui; Xu, Zhuodong; Wu, Lebin; Cheng, Zhaoping; Ji, Xiaopeng; Zhong, Hai; Meng, Chen

    2013-01-01

    OBJECTIVES: To assess the feasibility of low-dose prospective ECG-gated dual-source CT (DSCT) in detecting airway anomalies in pediatric patients with cardiovascular anomalies compared with flexible tracheobronchoscopy (FTB). METHODS: 33 pediatrics with respiratory symptoms who had been revealed cardiovascular anomalies by transthoracic echocardiography underwent FTB and contrast material-enhanced prospective ECG-triggering CT were enrolled. The study was approved by our institution review bo...

  11. Prospective ECG triggering versus low-dose retrospective ECG-gated 128-channel CT coronary angiography: comparison of image quality and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Q.; Yin, Y.; Hua, X.; Zhu, R.; Hua, J. [Department of Radiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Xu, J., E-mail: xujianr@hotmail.co [Department of Radiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China)

    2010-10-15

    Aim: To evaluate image quality and radiation dose for 128-detector prospective electrocardiogram (ECG)-gated computed tomography coronary angiography (CTCA) compared with a low-dose retrospective ECG-gated imaging protocol. Materials and methods: Thirty-one and 47 patients suspected of having coronary artery disease were enrolled into groups examined using prospective and low-dose retrospective ECG-gated CT protocols respectively. All examinations were performed on a 128-detector CT system (Definition AS, Siemens Healthcare, Forchheim, Germany). Prospective CTCA was performed using following parameters: tube voltage 100 kV; tube current 205 mAs; centre of acquisition window 70% of the RR interval. The tube current for low-dose retrospective ECG-gated CTCA was full dose during 40-70% of the RR interval and partial dose for the rest of RR interval. The pitch varied between 0.2 and 0.5 depending on heart rate and patient size. Image quality of coronary arteries was evaluated using a four-point grading scale. The signal-to-noise ratios (SNRs) of enhanced arteries and myocardium were also measured, corresponding contrast-to-noise ratios (CNRs) were calculated, and the radiation doses received were recorded. Results: There was a significant difference in the image quality scores between the retrospective and prospective gating protocols (Chi-square = 15.331, p = 0.009). There was no significant difference between the SNRs of the contrasted artery and myocardium in these two groups, but the CNRs were increased in the prospective group. The mean radiation dose of prospective gating group was 2.71 {+-} 0.67 mSv (range, 1.67-3.59 mSv), which was significantly lower than that of the retrospective group (p < 0.001). Conclusion: Prospective CT angiography can achieve lower radiation dose than that of low-dose retrospective CT angiography, with preserved image quality.

  12. AMINO ACID BLOOD POOL OF CHILDREN WITH ALLERGIC DISEASES

    Directory of Open Access Journals (Sweden)

    Shmulich O. V.

    2014-01-01

    Full Text Available The amino acid blood pool of children with atopic dermatitis, bronchial asthma, urticaria, angioedema was investigated. The variability of blood plasma amino acid content (tryptophan, histidine, tyrosine, cysteine, methionine was observed. The changes of histidine and tryptophan levels might be connected with the formation of biogenic amines, such as histamine, serotonine, with take part in the development of allergic reactions and inflammatory processes in organism.

  13. Comprehensive cardiovascular ECG-gated MDCT as a standard diagnostic tool in patients with acute chest pain

    International Nuclear Information System (INIS)

    Runza, G.; La Grutta, L.; Alaimo, V.; Evola, S.; Lo Re, F.; Bartolotta, T.V.; Cademartiri, F.; Midiri, M.

    2007-01-01

    Acute myocardial infarction, pulmonary embolism, and aortic dissection are diseases associated with acute chest pain and may lead to severe morbidity and mortality. These diseases may not be trivial to diagnose in the settings of emergency room. ECG-gated multi-detector computed tomography (MDCT), already established for the assessment of pulmonary embolism and aortic dissection, provides reliable information regarding the triage of patients with acute coronary syndrome in the emergency room. MDCT recently appeared to be logistically feasible and a promising comprehensive method for the evaluation of cardiac and non-cardiac chest pain in emergency department patients. The possibility to scan the entire thorax visualizing the thoracic aorta, the pulmonary arteries, and the coronary arteries could provide a new approach to the triage of acute chest pain. The inherent advantage of MDCT with cardiac state-of-the-art capabilities is the rapid investigation of the main sources of acute chest pain with a high negative predictive value. Recent studies also reports an advantage in terms of costs. With current evidence, the selection of patients with acute chest pain candidates to MDCT should remain restricted to avoid unjustified risk of ionizing radiation

  14. Comprehensive cardiovascular ECG-gated MDCT as a standard diagnostic tool in patients with acute chest pain

    Energy Technology Data Exchange (ETDEWEB)

    Runza, G. [Department of Radiology, University of Palermo (Italy)], E-mail: grunza@sirm.org; La Grutta, L.; Alaimo, V. [Department of Radiology, University of Palermo (Italy); Evola, S. [Department of Cardiology, University of Palermo (Italy); Lo Re, F.; Bartolotta, T.V. [Department of Radiology, University of Palermo (Italy); Cademartiri, F. [Department of Radiology and Cardiology, Erasmus Medical Center, Rotterdam (Netherlands); Department of Radiology and Cardiology, Cardiovascular CT Unit, University Hospital, Parma (Italy); Midiri, M. [Department of Radiology, University of Palermo (Italy)

    2007-10-15

    Acute myocardial infarction, pulmonary embolism, and aortic dissection are diseases associated with acute chest pain and may lead to severe morbidity and mortality. These diseases may not be trivial to diagnose in the settings of emergency room. ECG-gated multi-detector computed tomography (MDCT), already established for the assessment of pulmonary embolism and aortic dissection, provides reliable information regarding the triage of patients with acute coronary syndrome in the emergency room. MDCT recently appeared to be logistically feasible and a promising comprehensive method for the evaluation of cardiac and non-cardiac chest pain in emergency department patients. The possibility to scan the entire thorax visualizing the thoracic aorta, the pulmonary arteries, and the coronary arteries could provide a new approach to the triage of acute chest pain. The inherent advantage of MDCT with cardiac state-of-the-art capabilities is the rapid investigation of the main sources of acute chest pain with a high negative predictive value. Recent studies also reports an advantage in terms of costs. With current evidence, the selection of patients with acute chest pain candidates to MDCT should remain restricted to avoid unjustified risk of ionizing radiation.

  15. Coronary imaging quality in routine ECG-gated multidetector CT examinations of the entire thorax: preliminary experience with a 64-slice CT system in 133 patients

    International Nuclear Information System (INIS)

    Delhaye, Damien; Remy-Jardin, Martine; Salem, Randa; Teisseire, Antoine; Khalil, Chadi; Remy, Jacques; Delannoy-Deken, Valerie; Duhamel, Alain

    2007-01-01

    To evaluate image quality in the assessment of the coronary arteries during routine ECG-gated multidetector CT (MDCT) of the chest. One hundred and thirty three patients in sinus rhythm underwent an ECG-gated CT angiographic examination of the entire chest without β-blockers with a 64-slice CT system. In 127 patients (95%), it was possible to assess the coronary arteries partially or totally; coronary artery imaging failed in six patients (5%), leading to a detailed description of the coronary arteries in 127 patients. Considering ten coronary artery segments per patient, 75% of coronary segments were assessable (948/1270 segments). When the distal segments were excluded from the analysis (i.e., seven coronary segments evaluated per patient), the percentage of assessable segments was 86% (768/889 proximal and mid coronary segments) and reached 93% (474/508) when assessing proximal segments exclusively. The mean number of assessable segments was significantly higher in patients with a heart rate ≤80 bpm (n=95) than in patients with a heart rate >80 bpm (n=38) (p<0.002). Proximal and mid-coronary segments can be adequately assessed during a whole-chest ECG-gated CT angiographic examination without administration of β-blockers in patients with a heart rate below 80 bpm. (orig.)

  16. The value of low-dose prospective ECG-gated dual-source CT angiography in the diagnosis of coarctation of the aorta in infants and children

    Energy Technology Data Exchange (ETDEWEB)

    Nie, P. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Wang, X., E-mail: wxming369@yahoo.com.cn [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Cheng, Z.; Duan, Y.; Ji, X. [Shandong Provincial Key Laboratory of Diagnosis and Treatment of Cardio-Cerebral Vascular Diseases, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong (China); Chen, J. [CT Research Collaboration, Siemens, Beijing (China); Zhang, H. [Department of Cardiovascular Surgery, Shandong Provincial Hospital, Jinan, Shandong (China)

    2012-08-15

    Aim: To investigate the value of prospective electrocardiogram (ECG)-gated dual-source computed tomography (DSCT) in the diagnosis of coarctation of the aorta (CoA). Materials and methods: Seventeen patients clinically suspected of having CoA underwent prospective ECG-gated DSCT angiography and transthoracic echocardiography (TTE). Surgery was performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared with the surgical findings as the reference standard. Image quality was evaluated using a five-point scale. Effective radiation dose was calculated from the dose-length product (DLP). Results: CoA was diagnosed in 17 patients by DSCT angiography and in 16 patients by TTE. A total of 46 separate cardiovascular abnormalities were confirmed by surgical findings. The diagnostic accuracy of DSCT angiography and TTE was 96.32% and 97.06%, respectively. There was no significant difference in the diagnostic accuracy between DSCT angiography and TTE ({chi}{sup 2} = 0, p > 0.05). The mean score of image quality was 4.2 {+-} 0.8. The mean effective dose was 0.69 {+-} 0.09 mSv. Conclusion: Prospective ECG-gated DSCT with a low radiation dose is a valuable technique in the diagnosis of CoA in infants and children.

  17. Myocardial enhancement pattern in patients with acute myocardial infarction on two-phase contrast-enhanced Ecg-gated multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Ko, S.M.; Seo, J.B.; Hong, M.K.; Do, K.H.; Lee, S.H.; Lee, J.S.; Song, J.W.; Park, S.J.; Park, S.W.; Lim, T.H.

    2006-01-01

    Aim: To evaluate the myocardial enhancement pattern of the left ventricle on two-phase contrast-enhanced electrocardiogram (ECG)-gated multidetector computed tomography (MDCT) images in patients with acute myocardial infarction (AMI). METHODS: Two-phase contrast-enhanced ECG-gated MDCT examinations were performed in 16 patients with AMI. The presence, location and pattern of myocardial enhancement were evaluated. MDCT findings were compared with the catheter angiographic results. RESULTS: Subendocardial (n=9) or transmural (n=6) area of early perfusion defects of the myocardium was detected in 15 of 16 patients (94%) on early-phase CT images. Variable delayed myocardial enhancement patterns on late-phase CT images were observed in 12 patients (75%): (1) subendocardial residual perfusion defect and subepicardial late enhancement (n=6); (2) transmural late enhancement (n=1); (3) isolated subendocardial late enhancement (n=1); and (4) isolated subendocardial residual perfusion defect (n=2). On catheter angiography, 14 of 15 corresponding coronary arteries showed significant stenosis. CONCLUSION: Variable abnormal myocardial enhancement pattern was seen on two-phase, contrast-enhanced ECG-gated MDCT in patients with AMI. Assessment of myocardial attenuation on CT angiography gives additional information of the location and extent of infarction

  18. Evaluation of hepatic hemangioma by Tc-99 m red blood cell hepatic blood pool scan

    International Nuclear Information System (INIS)

    Sohn, Myung Hee

    2005-01-01

    Hemangioma is the most common benign tumor of the liver, with a prevalence estimated as high as 7%. Tc-99m red blood cell (RBC) hepatic blood pool scan with single photon emission computed tomography (SPECT) imaging is extremely useful for the confirmation or exclusion of hepatic hemangiomas. The classic finding of absent or decreased perfusion and increased blood pooling ('perfusion/blood pool mismatch') is the key diagnostic element in the diagnosis of hemangiomas. The combination of early arterial flow and delayed blood pooling ('perfusion/blood pool match') is shown uncommonly. In giant hemangioma, filling with radioactivity appears first in the periphery, with progressive central fill-in on sequential RBC blood pool scan. However, the reverse filling pattern, which begins first in the center with progressive peripheral filling, is also rarely seen. Studies with false-positive blood pooling have been reported infrequently in nonhemangiomas, including hemangiosarcoma, hepatocellular carcinoma, hepatic adenoma, and metastatic carcinomas (adenocarcinma of the colon, small cell carcinoma of the lung, neruroendocrine carcinoma). False-negative results have been also reported rarely except for small hemagniomas that are below the limits of spatial resolution of gamma camera

  19. MO-DE-207A-06: ECG-Gated CT Reconstruction for a C-Arm Inverse Geometry X-Ray System

    Energy Technology Data Exchange (ETDEWEB)

    Slagowski, JM; Dunkerley, DAP [MA Speidel, University of Wisconsin - Madison, Madison, WI (United States)

    2016-06-15

    Purpose: To obtain ECG-gated CT images from truncated projection data acquired with a C-arm based inverse geometry fluoroscopy system, for the purpose of cardiac chamber mapping in interventional procedures. Methods: Scanning-beam digital x-ray (SBDX) is an inverse geometry fluoroscopy system with a scanned multisource x-ray tube and a photon-counting detector mounted to a C-arm. In the proposed method, SBDX short-scan rotational acquisition is performed followed by inverse geometry CT (IGCT) reconstruction and segmentation of contrast-enhanced objects. The prior image constrained compressed sensing (PICCS) framework was adapted for IGCT reconstruction to mitigate artifacts arising from data truncation and angular undersampling due to cardiac gating. The performance of the reconstruction algorithm was evaluated in numerical simulations of truncated and non-truncated thorax phantoms containing a dynamic ellipsoid to represent a moving cardiac chamber. The eccentricity of the ellipsoid was varied at frequencies from 1–1.5 Hz. Projection data were retrospectively sorted into 13 cardiac phases. Each phase was reconstructed using IGCT-PICCS, with a nongated gridded FBP (gFBP) prior image. Surface accuracy was determined using Dice similarity coefficient and a histogram of the point distances between the segmented surface and ground truth surface. Results: The gated IGCT-PICCS algorithm improved surface accuracy and reduced streaking and truncation artifacts when compared to nongated gFBP. For the non-truncated thorax with 1.25 Hz motion, 99% of segmented surface points were within 0.3 mm of the 15 mm diameter ground truth ellipse, versus 1.0 mm for gFBP. For the truncated thorax phantom with a 40 mm diameter ellipse, IGCT-PICCS surface accuracy measured 0.3 mm versus 7.8 mm for gFBP. Dice similarity coefficient was 0.99–1.00 (IGCT-PICCS) versus 0.63–0.75 (gFBP) for intensity-based segmentation thresholds ranging from 25–75% maximum contrast. Conclusions: The

  20. Quantification of left ventricular regional functions using ECG-gated myocardial perfusion SPECT. Validation of left ventricular systolic functions

    International Nuclear Information System (INIS)

    Yamamoto, Akira; Takahashi, Naoto; Iwahara, Shin-ichiro; Munakata, Kazuo; Hosoya, Tetsuo

    2006-01-01

    We have developed a program to quantify regional left ventricular (LV) function and wall motion synchrony using electrocardiogram (ECG)-gated myocardial perfusion SPECT (MPS). This preliminary study was undertaken to validate the use of this program for estimating regional LV systolic function. Patients were subjected to MPS by 99m Tc-sestamibi at rest. The study included 20 patients who were confirmed to have a low probability of coronary artery disease (LPG; low probability group), 19 heart disease patients who were examined by MPS and equilibrium radionuclide angiography (ERNA) (ERG; ERNA group), and 24 patients who were examined by MPS and 2-dimensional echocardiography (2DE) (2DEG; 2DE group). The values of the ejection fraction (EF) and peak ejection rate (PER) were estimated. The global functions evaluated by this program were compared with those obtained by ERNA in the ERG. For regional assessment, the reference values of the functional indices were obtained for 17 LV segments in LPG. The Z score, (reference average value of the segment-patient's value of the segment)/reference standard deviation of the segment, was used for the evaluation of regional functions; a score equal to or greater than 2 was defined as abnormal. Semiquantitative visual interpretation of 2DE was used as the standard to assess wall motion. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these criteria and the relationship between 2DE grading and Z scoring were validated in 2DEG. The values of the global EF and PER evaluated by this program correlated with those determined by ERNA (r=0.76 and 0.58, respectively; p -10 ). The potential of this program to quantify the regional systolic function was validated. (author)

  1. Accuracy and reliability of noninvasive stroke volume monitoring via ECG-gated 3D electrical impedance tomography in healthy volunteers

    Science.gov (United States)

    Proença, Martin; Adler, Andy; Riedel, Thomas; Thiran, Jean-Philippe; Solà, Josep

    2018-01-01

    Cardiac output (CO) and stroke volume (SV) are parameters of key clinical interest. Many techniques exist to measure CO and SV, but are either invasive or insufficiently accurate in clinical settings. Electrical impedance tomography (EIT) has been suggested as a noninvasive measure of SV, but inconsistent results have been reported. Our goal is to determine the accuracy and reliability of EIT-based SV measurements, and whether advanced image reconstruction approaches can help to improve the estimates. Data were collected on ten healthy volunteers undergoing postural changes and exercise. To overcome the sensitivity to heart displacement and thorax morphology reported in previous work, we used a 3D EIT configuration with 2 planes of 16 electrodes and subject-specific reconstruction models. Various EIT-derived SV estimates were compared to reference measurements derived from the oxygen uptake. Results revealed a dramatic impact of posture on the EIT images. Therefore, the analysis was restricted to measurements in supine position under controlled conditions (low noise and stable heart and lung regions). In these measurements, amplitudes of impedance changes in the heart and lung regions could successfully be derived from EIT using ECG gating. However, despite a subject-specific calibration the heart-related estimates showed an error of 0.0 ± 15.2 mL for absolute SV estimation. For trending of relative SV changes, a concordance rate of 80.9% and an angular error of −1.0 ± 23.0° were obtained. These performances are insufficient for most clinical uses. Similar conclusions were derived from lung-related estimates. Our findings indicate that the key difficulty in EIT-based SV monitoring is that purely amplitude-based features are strongly influenced by other factors (such as posture, electrode contact impedance and lung or heart conductivity). All the data of the present study are made publicly available for further investigations. PMID:29373611

  2. A comparison of positron-emitting blood pool imaging agents

    International Nuclear Information System (INIS)

    Hnatowich, D.J.; Kulprathipanja, S.; Evans, G.; Elmaleh, D.

    1979-01-01

    The three agents, 11 C-carboxyhaemoglobin, 68 Ga-transferrin and 68 Ga-labelled red cells have been compared in dogs to assess their relative merits for blood-pool imaging. For 1 h following administration of each agent, periodic blood samples were withdrawn for counting in a NaI (Tl) well counter while conventional two-dimensional images were obtained simultaneously on the Massachusetts General Hospital positron camera. Count rates in regions about the heart, liver and spleen were obtained for each image. The disappearance of blood activity as shown from the results of counting the blood samples and from the counting rates in regions about the heart was found to be identical within experimental error for the three agents. In the liver and spleen regions, the highest count rates were obtained with 68 Ga-transferrin and the lowest with 68 Ga-labelled red cells; count rates in these regions with labelled red cells were virtually constant throughout the 1 h study. It may be concluded that with the exceptions noted above, the three agents are approximately equivalent for blood-pool imaging. (author)

  3. Noninvasive assessment of coronary artery disease by multislice spiral computed tomography using a new retrospectively ECG-gated image reconstruction technique. Comparison with angiographic results

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yuichi; Matsumoto, Naoya; Kato, Masahiko [Nihon Univ., Tokyo (Japan). Surugadai Hospital] [and others

    2003-04-01

    The present study was designed to investigate the accuracy of multislice spiral computed tomography (MSCT) in detecting coronary artery disease, compared with coronary angiography (CAG), using a new retrospectively ECG-gated reconstruction method that reduced cardiac motion artifact. The study group comprised 54 consecutive patients undergoing MSCT and CAG. MSCT was performed using a SOMATOM Volume Zoom (4-detector-row, Siemens, Germany) with slice thickness 1.0 mm, pitch 1.5 (table feed: 1.5 mm per rotation) and gantry rotation time 500 ms. Metoprolol (20-60 mg) was administered orally prior to MSCT imaging. ECG-gated image reconstruction was performed with the reconstruction window (250 ms) positioned immediately before atrial contraction in order to reduce the cardiac motion artifact caused by the abrupt diastolic ventricular movement occurring during the rapid filling and atrial contraction periods. Following inspection of the volume rendering images, multiplanar reconstruction images and axial images of the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCx) and right coronary artery (RCA) were obtained and evaluated for luminal narrowing. The results were compared with those obtained by CAG. Of 216 coronary arteries, 206 (95.4%) were assessable; 10 arteries were excluded from the analysis because of severe calcification (n=4), stents (n=3) or insufficient contrast enhancement (n=3). The sensitivity to detect coronary stenoses {>=}50% was 93.5% and the specificity to define luminal narrowing <50% was 97.2%. The positive predictive value and the negative predictive value were 93.5% and 97.2%, respectively. The sensitivity was still satisfactory (80.6%) even when non-assessable arteries were included in the analysis. The new retrospectively ECG-gated reconstruction method for MSCT has excellent diagnostic accuracy in detecting significant coronary artery stenoses. (author)

  4. 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.

  5. Dried blood spots of pooled samples for RHD gene screening in blood donors of mixed ancestry.

    Science.gov (United States)

    Silva-Malta, M C F; Araujo, N C Fidélis; Vieira, O V Neves; Schmidt, L Cayres; Gonçalves, P de Cassia; Martins, M Lobato

    2015-10-01

    In this study, we present a strategy for RHD gene screening based on real-time polymerase chain reaction (PCR) using dried blood spots of pooled samples. Molecular analysis of blood donors may be used to detect RHD variants among the presumed D-negative individuals. RHD genotyping using pooled samples is a strategy to test a large number of samples at a more reasonable cost. RHD gene detection based on real-time PCR using dried blood spots of pooled samples was standardised and used to evaluate 1550 Brazilian blood donors phenotyped as RhD-negative. Positive results were re-evaluated by retesting single samples using real-time PCR and conventional multiplex PCR to amplify five RHD-specific exons. PCR-sequence-specific primers was used to amplify RHDψ allele. We devised a strategy for RHD gene screening using dried blood spots of five pooled samples. Among 1550 serologically D-negative blood donors, 58 (3.74%) had the RHD gene. The non-functional RHDψ allele was detected in 47 samples (3.02%). The present method is a promising strategy to detect the RHD gene among presumed RhD-negative blood donors, particularly for populations with African ancestry. © 2015 British Blood Transfusion Society.

  6. Evaluation of the retrospective ECG-gated helical scan using half-second multi-slice CT. Motion phantom study for volumetry

    International Nuclear Information System (INIS)

    Yamamoto, Shuji; Matsumoto, Takashi; Nakanishi, Shohzoh; Hamada, Seiki; Takahei, Kazunari; Naito, Hiroaki; Ogata, Yuji

    2002-01-01

    ECG synchronized technique on multi-slice CT provide the thinner (less 2 mm slice thickness) and faster (0.5 sec/rotation) scan than that of the single detector CT and can acquire the coverage of the entire heart volume within one breath-hold. However, temporal resolution of multi-slice CT is insufficient on practical range of heart rate. The purpose of this study was to evaluate the accuracy of volumetry on cardiac function measurement in retrospective ECG-gated helical scan. We discussed the influence of the degradation of image quality and limitation of the heart rate in cardiac function measurement (volumetry) using motion phantom. (author)

  7. Gated blood pool scintigraphy in patients with valvular heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Breuel, H.P.; Heusinger, J.H.; Hanisch, K.

    1984-10-01

    In 58 patients suffering from either stenosis or insufficiency of a single heart valve, gated blood pool scintigraphy was performed to determine the ejection fraction as well as the peak filling and peak ejection rates. It could be demonstrated that in patients with valvular disorders the ejection fraction was only moderately decreased, generally remaining in the lower reference range. The peak filling and ejection rates showed no pathologic changes with the exception of patients with aortic regurgitation where these rates were significantly decreased. Thus, the estimation of left ventricular peak filling and ejection rates may permit diagnosis of myocardial impairment in patients with valvular disease even under resting conditions.

  8. Value of 3D-Volume Rendering in the Assessment of Coronary Arteries with Retrospectively Ecg-Gated Multislice Spiral CT

    International Nuclear Information System (INIS)

    Mahnken, A.H.; Wildberger, J.E.; Dedden, K.; Schmitz-Rode, T.; Guenther, R.W.; Sinha, A.M.; Hoffmann, R.; Stanzel, S.

    2003-01-01

    Purpose: To assess the diagnostic value and measurement precision of 3D volume rendering technique (3D-VRT) from retrospectively ECG-gated multislice spiral CT (MSCT) data sets for imaging of the coronary arteries. Material and Methods: In 35 patients, retrospectively ECG-gated MSCT of the heart using a four detector row MSCT scanner with a standardized examination protocol was performed as well as quantitative X-ray coronary angiography (QCA). The MSCT data was assessed on segmental basis using 3D-VRT exclusively. The coronary artery diameters were measured at the origin of each main coronary branch and 1 cm, 3 cm and 5 cm distally. The minimum, maximum and mean diameters were determined from MSCT angiography and compared to QCA. Results: A total of 353 of 525 (67.2%) coronary artery segments were assessable by MSCT angiography. The proximal segments were more often assessable when compared to the distal segments. Stenoses were detected with a sensitivity of 82.6% and a specificity of 92.8%. According to the Bland-Altman method the mean differences between QCA and MSCT ranged from 0.55 to 1.07 mm with limits of agreement from 2.2 mm to 2.7 mm. Conclusion: When compared to QCA, the ability of 3D-VRT to quantitatively assess coronary artery diameters and coronary artery stenoses is insufficient for clinical purposes

  9. Prospectively ECG-triggered sequential dual-source coronary CT angiography in patients with atrial fibrillation: comparison with retrospectively ECG-gated helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei; Yang, Lin; Zhang, Zhaoqi [Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Wang, Yining; Jin, Zhengyu [Chinese Academy of Medical Sciences, Department of Radiology, Peking Union Medical College Hospital, Beijing (China); Zhang, Longjiang; Lu, Guangming [Nanjing University, Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing, Jiangsu (China)

    2013-07-15

    To investigate the feasibility of applying prospectively ECG-triggered sequential coronary CT angiography (CCTA) to patients with atrial fibrillation (AF) and evaluate the image quality and radiation dose compared with a retrospectively ECG-gated helical protocol. 100 patients with persistent AF were enrolled. Fifty patients were randomly assigned to a prospective protocol and the other patients to a retrospective protocol using a second-generation dual-source CT (DS-CT). Image quality was evaluated using a four-point grading scale (1 = excellent, 2 = good, 3 = moderate, 4 = poor) by two reviewers on a per-segment basis. The coronary artery segments were considered non-diagnostic with a quality score of 4. The radiation dose was evaluated. Diagnostic segment rate in the prospective group was 99.4 % (642/646 segments), while that in the retrospective group was 96.5 % (604/626 segments) (P < 0.001). Effective dose was 4.29 {+-} 1.86 and 11.95 {+-} 5.34 mSv for each of the two protocols (P < 0.001), which was a 64 % reduction in the radiation dose for prospective sequential imaging compared with retrospective helical imaging. In AF patients, prospectively ECG-triggered sequential CCTA is feasible using second-generation DS-CT and can decrease >60 % radiation exposure compared with retrospectively ECG-gated helical imaging while improving diagnostic image quality. (orig.)

  10. Nonenhanced ECG-gated quiescent-interval single-shot MRA (QISS-MRA) of the lower extremities: Comparison with contrast-enhanced MRA

    Energy Technology Data Exchange (ETDEWEB)

    Klasen, J. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Blondin, D., E-mail: blondin@med.uni-duesseldorf.de [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Schmitt, P. [Siemens AG, Healthcare Sector, Erlangen (Germany); Bi, X. [Siemens Healthcare, Chicago, IL (United States); Sansone, R. [Department of Cardiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Wittsack, H.-J.; Kroepil, P.; Quentin, M.; Kuhlemann, J.; Miese, F. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Heiss, C.; Kelm, M. [Department of Cardiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany); Antoch, G.; Lanzman, R.S. [Department of Diagnostic and Interventional Radiology, University of Duesseldorf, Medical Faculty, Duesseldorf (Germany)

    2012-05-15

    Aim: To evaluate electrocardiogram (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) for nonenhanced assessment of peripheral artery occlusive disease (PAOD) using contrast-enhanced MRA (CE-MRA) as the reference standard. Materials and methods: Twenty-seven patients (mean age 66.6 {+-} 10.8 years) with PAOD were included in the study. QISS-MRA and CE-MRA of the lower extremity were performed using a 1.5 T MR scanner. In each patient, subjective image quality and the degree of stenosis were evaluated on a four-point scale for 15 predefined arterial segments. Results: Twenty-five of the 27 patients were considered for analysis. Subjective image quality of QISS-MRA was significantly lower for the distal aorta, pelvic arteries, and femoral arteries as compared to CE-MRA (p < 0.01), while no significant difference was found for other vascular segments. The degree of stenosis was overestimated with QISS-MRA in 23 of 365 (6.3%) segments and underestimated in two of 365 (0.5%) segments. As compared to CE-MRA, QISS-MRA had a high sensitivity (98.6%), specificity (96%) as well as positive and negative predictive value (88.7 and 99.6%, respectively) for the detection of significant stenosis ({>=}50%). Conclusion: ECG-gated QISS-MRA is a promising imaging technique for reliable assessment of PAOD without the use of contrast material.

  11. Nonenhanced ECG-gated quiescent-interval single-shot MRA (QISS-MRA) of the lower extremities: Comparison with contrast-enhanced MRA

    International Nuclear Information System (INIS)

    Klasen, J.; Blondin, D.; Schmitt, P.; Bi, X.; Sansone, R.; Wittsack, H.-J.; Kröpil, P.; Quentin, M.; Kuhlemann, J.; Miese, F.; Heiss, C.; Kelm, M.; Antoch, G.; Lanzman, R.S.

    2012-01-01

    Aim: To evaluate electrocardiogram (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) for nonenhanced assessment of peripheral artery occlusive disease (PAOD) using contrast-enhanced MRA (CE-MRA) as the reference standard. Materials and methods: Twenty-seven patients (mean age 66.6 ± 10.8 years) with PAOD were included in the study. QISS-MRA and CE-MRA of the lower extremity were performed using a 1.5 T MR scanner. In each patient, subjective image quality and the degree of stenosis were evaluated on a four-point scale for 15 predefined arterial segments. Results: Twenty-five of the 27 patients were considered for analysis. Subjective image quality of QISS-MRA was significantly lower for the distal aorta, pelvic arteries, and femoral arteries as compared to CE-MRA (p < 0.01), while no significant difference was found for other vascular segments. The degree of stenosis was overestimated with QISS-MRA in 23 of 365 (6.3%) segments and underestimated in two of 365 (0.5%) segments. As compared to CE-MRA, QISS-MRA had a high sensitivity (98.6%), specificity (96%) as well as positive and negative predictive value (88.7 and 99.6%, respectively) for the detection of significant stenosis (≥50%). Conclusion: ECG-gated QISS-MRA is a promising imaging technique for reliable assessment of PAOD without the use of contrast material.

  12. Three-dimensional thoracic aorta principal strain analysis from routine ECG-gated computerized tomography: feasibility in patients undergoing transcatheter aortic valve replacement.

    Science.gov (United States)

    Satriano, Alessandro; Guenther, Zachary; White, James A; Merchant, Naeem; Di Martino, Elena S; Al-Qoofi, Faisal; Lydell, Carmen P; Fine, Nowell M

    2018-05-02

    Functional impairment of the aorta is a recognized complication of aortic and aortic valve disease. Aortic strain measurement provides effective quantification of mechanical aortic function, and 3-dimenional (3D) approaches may be desirable for serial evaluation. Computerized tomographic angiography (CTA) is routinely performed for various clinical indications, and offers the unique potential to study 3D aortic deformation. We sought to investigate the feasibility of performing 3D aortic strain analysis in a candidate population of patients undergoing transcatheter aortic valve replacement (TAVR). Twenty-one patients with severe aortic valve stenosis (AS) referred for TAVR underwent ECG-gated CTA and echocardiography. CTA images were analyzed using a 3D feature-tracking based technique to construct a dynamic aortic mesh model to perform peak principal strain amplitude (PPSA) analysis. Segmental strain values were correlated against clinical, hemodynamic and echocardiographic variables. Reproducibility analysis was performed. The mean patient age was 81±6 years. Mean left ventricular ejection fraction was 52±14%, aortic valve area (AVA) 0.6±0.3 cm 2 and mean AS pressure gradient (MG) 44±11 mmHg. CTA-based 3D PPSA analysis was feasible in all subjects. Mean PPSA values for the global thoracic aorta, ascending aorta, aortic arch and descending aorta segments were 6.5±3.0, 10.2±6.0, 6.1±2.9 and 3.3±1.7%, respectively. 3D PSSA values demonstrated significantly more impairment with measures of worsening AS severity, including AVA and MG for the global thoracic aorta and ascending segment (panalysis is clinically feasible from routine ECG-gated CTA. Appropriate reductions in PSSA were identified with increasing AS hemodynamic severity. Expanded study of 3D aortic PSSA for patients with various forms of aortic disease is warranted.

  13. Diagnostic value of early post-exercise 99Tcm-MIBI ECG-gated myocardial perfusion imaging in severe coronary artery disease

    International Nuclear Information System (INIS)

    Li Dianfu; Huang Jun; Feng Jianlin; Cheng Xu; Li Xinli; Cao Kejiang

    2005-01-01

    Objective: To study and compare the diagnostic value in severe coronary artery disease (CAD) of 99 Tc m -methoxyisobutylisonitrile (MIBI) electrocardiogram (ECG)-gated early post-exercise myocardial perfusion imaging (G-MPI) with that of non-ECG-gated myocardial perfusion imaging (NG-MPI). Methods: Two hundred and fifteen suspected CAD patients had undergone G-MPI and coronary artery angiography (CAG) within one month were enrolled and distributed into three-vessel and non-three-vessel CAD groups according to CAG results (≥70%); the diagnostic values in severe CAD of G-MPI and NG-MPI were gained and compared to determine which one of the two protocols would be superior in identification of severe three-vessel CAD. Results: When the ≥70% diameter stenosis CAG was the diagnostic standard of severe CAD, the sensitivity of G-MPI and NG-MPI in the diagnosis of severe CAD were 95.3% (143/150) and 90.7% (136/150, χ 2 =2.509, P=0.113), but when the comparison specifically pinpointed to severe three-vessel CAD, there was significant difference between G-MPI [100%(51/51)] and NG-MPI [92.2% (47/51), χ 2 =4.163, P=0.041]. Diagnostic specificity of G-MPI was 80.0% and that of NG-MPI was 72.3% (χ 2 =1.059, P=0.303). Conclusions: The incremental diagnostic sensitivity of G-MPI adding to the NG-MPI in the diagnosis of severe CAD was mainly from the three-vessel subgroup patients. Exercise stress G-MPI has better diagnostic value in severe three-vessel CAD patients than NG-MPI. (authors)

  14. Prospective versus retrospective ECG gating for dual source CT of the coronary stent: Comparison of image quality, accuracy, and radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Lei, E-mail: zhaolei219@sohu.com [Beijing Anzhen Hospital of the Capital University of Medical Sciences (China); Zhang Zhaoqi; Fan Zhanming; Yang Lin; Du Jing [Beijing Anzhen Hospital of the Capital University of Medical Sciences (China)

    2011-03-15

    Objective: To compare image quality, diagnostic accuracy and radiation dose of prospective and retrospective electrocardiogram (ECG) gated dual source computed tomography (DSCT) for the evaluation of the coronary stent, using conventional coronary angiography (CA) as a standard reference. Design, setting and patients: Sixty patients (heart rates {<=}70 bpm) with previous stent implantation who were scheduled for CA were divided in two groups, receiving either prospective or retrospective ECG gated DSCT separately. Two reviewers scored coronary stent image quality and evaluated stent lumen. Results: There was no significant difference in image quality between the two groups. In the prospective group, there were 86.4% (51/59) stents with interpretable images, in the retrospective group, there were 87.5% (49/56) stents with interpretable images. Image quality was not influenced by age, body mass index or heart rate in either group, but heart rate variability had a weak impact on the image quality of the prospective group. Image noise was higher in the prospective group, but this difference reached statistical significance only by using a smooth kernel reconstruction. Per-stent based sensitivity, specificity, and positive and negative predictive value were 100%, 84.1%, 68.2%, and 100%, respectively, in the prospective CT angiography group and 94.4%, 86.8%, 77.3%, and 97.1%, respectively, in the retrospective CT angiography group. There was a significant difference in the effective radiation dose between the two groups, mean effective dose in the prospective and retrospective group was 2.2 {+-} 0.5 mSv (1.5-3.2 mSv) and 14.6 {+-} 3.3 mSv (10.0-20.4 mSv) (p < .001) respectively. Conclusions: Compared with retrospective CT angiography, prospective CT angiography has a similar performance in assessing coronary stent patency, but a lower effective dose in selected patients with regular heart rates {<=}70 bpm.

  15. Study on motion artifacts in coronary arteries with an anthropomorphic moving heart phantom on an ECG-gated multidetector computed tomography unit

    International Nuclear Information System (INIS)

    Greuter, Marcel J.W.; Dorgelo, Joost; Tukker, Wim G.J.; Oudkerk, Matthijs

    2005-01-01

    Acquisition time plays a key role in the quality of cardiac multidetector computed tomography (MDCT) and is directly related to the rotation time of the scanner. The purpose of this study is to examine the influence of heart rate and a multisector reconstruction algorithm on the image quality of coronary arteries of an anthropomorphic adjustable moving heart phantom on an ECG-gated MDCT unit. The heart phantom and a coronary artery phantom were used on a MDCT unit with a rotation time of 500 ms. The movement of the heart was determined by analysis of the images taken at different phases. The results indicate that the movement of the coronary arteries on the heart phantom is comparable to that in a clinical setting. The influence of the heart rate on image quality and artifacts was determined by analysis of several heart rates between 40 and 80 bpm where the movement of the heart was synchronized using a retrospective ECG-gated acquisition protocol. The resulting reformatted volume rendering images of the moving heart and the coronary arteries were qualitatively compared as a result of the heart rate. The evaluation was performed on three independent series by two independent radiologists for the image quality of the coronary arteries and the presence of artifacts. The evaluation shows that at heart rates above 50 bpm the influence of motion artifacts in the coronary arteries becomes apparent. In addition the influence of a dedicated multisector reconstruction technique on image quality was determined. The results show that the image quality of the coronary arteries is not only related to the heart rate and that the influence of the multisector reconstruction technique becomes significant above 70 bpm. Therefore, this study proves that from the actual acquisition time per heart cycle one cannot determine an actual acquisition time, but only a mathematical acquisition time. (orig.)

  16. Prognostic significance of stress myocardial ECG-gated perfusion imaging in asymptomatic patients with diabetic chronic kidney disease on initiation of haemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Momose, Mitsuru; Kondo, Chisato; Kobayashi, Hideki; Kusakabe, Kiyoko [Tokyo Women' s Medical University, School of Medicine, Department of Radiology, Shinjuku-ku, Tokyo (Japan); Babazono, Tetsuya [Tokyo Women' s Medical University, School of Medicine, Diabetes Centre, Shinjuku-ku, Tokyo (Japan); Nakajima, Takatomo [Tokyo Women' s Medical University, School of Medicine, Department of Cardiology, Shinjuku-ku, Tokyo (Japan)

    2009-08-15

    Diabetic patients with chronic kidney disease (CKD) frequently develop cardiac events within several years of the initiation of haemodialysis. The present study assesses the prognostic significance of stress myocardial ECG-gated perfusion imaging (MPI) in patients with diabetic CKD requiring haemodialysis. Fifty-five asymptomatic patients with diabetic stage V CKD and no history of heart disease scheduled to start haemodialysis were enrolled in this study (56{+-}11 years old; 49 with type 2 diabetes mellitus). All patients underwent {sup 201}Tl stress ECG-gated MPI 1 month before or after the initiation of haemodialysis to assess myocardial involvement. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score (SSS) and summed difference scores (SDS). The patients were followed up for at least 2 years (42{+-}15 months) to determine coronary intervention (CI) and heart failure (HF) as soft events and acute myocardial infarction (AMI) and all causes of deaths as hard events. The frequencies of myocardial ischaemia, resting perfusion defects, low ejection fraction and left ventricular (LV) dilatation were 24,20,29 and 49%, respectively. Ten events (18%) developed during the follow-up period including four CI, one HF, one AMI and four sudden deaths. Multivariate Cox analysis selected SDS (p=0.0011) and haemoglobin A{sub 1c} (HbA{sub 1c}) (p=0.0076) as independent prognostic indicators for all events. Myocardial ischaemia, in addition to glycaemic control, is a strong prognostic marker for asymptomatic patients with diabetic CKD who are scheduled to start haemodialysis. Stress MPI is highly recommended for the management and therapeutic stratification of such patients. (orig.)

  17. Gated blood pool studies with a single probe - clinical validity

    International Nuclear Information System (INIS)

    Loesel, E.; Hoffmann, G.

    1981-01-01

    The global volume alterations of the heart can be estimated non-invasively by means of the radiocardiographic function analysis developed by Hoffmann and Kleine. Since the failing heart with its functional disturbances demonstrates a pathological volume behaviour under physical exercise, it is possible to use these characteristics to differentiate between the intact heart and the failing heart by registration of the global volume alterations. The gated blood pool technique combined with the registration of the intraventricular pressure pulse by means of a Swan-Ganz flow-directed catheter enables demonstration of ventricular stroke work as a pressure-volume loop (work diagram). Its shape indicates whether the ventricle has to perform mainly pressure work or volume work. Myocardial failure is altering the basic conditions of the heart. The work diagram of the failing heart is significantly different from that of the intact human heart. It is shifted in its pressure-volume coordinates according to an increase of EDV and ESV and the rise of the filling pressure. Case demonstrations reveal the global volume behaviour of the heart under varying conditions: resting and physical exercise, drug influence on the intact and failing heart. (orig.) [de

  18. Dose modulated retrospective ECG-gated versus non-gated 64-row CT angiography of the aorta at the same radiation dose: Comparison of motion artifacts, diagnostic confidence and signal-to-noise-ratios

    International Nuclear Information System (INIS)

    Schernthaner, Ruediger E.; Stadler, Alfred; Beitzke, Dietrich; Homolka, Peter; Weber, Michael; Lammer, Johannes; Czerny, Martin; Loewe, Christian

    2012-01-01

    Purpose: To compare ECG-gated and non-gated CT angiography of the aorta at the same radiation dose, with regard to motion artifacts (MA), diagnostic confidence (DC) and signal-to-noise-ratios (SNRs). Materials and methods: Sixty consecutive patients prospectively randomized into two groups underwent 64-row CT angiography, with or without dose-modulated ECG-gating, of the entire aorta, due to several pathologies of the ascending aorta. MA and DC were both assessed using a four-point scale. SNRs were calculated by dividing the mean enhancement by the standard deviation. The dose-length-product (DLP) of each examination was recorded and the effective dose was estimated. Results: Dose-modulated ECG-gating showed statistically significant advantages over non-gated CT angiography, with regard to MA (p < 0.001) and DC (p < 0.001), at the aortic valve, at the origin of the coronary arteries, and at the dissection membrane, with a significant correlation (p < 0.001) between MA and DC. At the aortic wall, however, ECG-gated CT angiography showed statistically significant fewer MA (p < 0.001), but not a statistically significant higher DC (p = 0.137) compared to non-gated CT angiography. At the supra-aortic vessels and the descending aorta, the ECG-triggering showed no statistically significant differences with regard to MA (p = 0.861 and 0.526, respectively) and DC (p = 1.88 and 0.728, respectively). The effective dose of ECG-gated CT angiography (23.24 mSv; range, 18.43–25.94 mSv) did not differ significantly (p = 0.051) from that of non-gated CT angiography (24.28 mSv; range, 19.37–29.27 mSv). Conclusion: ECG-gated CT angiography of the entire aorta reduces MA and results in a higher DC with the same SNR, compared to non-gated CT angiography at the same radiation dose.

  19. Nanoparticle encapsulation in red blood cells enables blood-pool magnetic particle imaging hours after injection

    International Nuclear Information System (INIS)

    Rahmer, J; Gleich, B; Borgert, J; Antonelli, A; Sfara, C; Magnani, M; Tiemann, B; Weizenecker, J

    2013-01-01

    Magnetic particle imaging (MPI) is a new medical imaging approach that is based on the nonlinear magnetization response of super-paramagnetic iron oxide nanoparticles (SPIOs) injected into the blood stream. To date, real-time MPI of the bolus passage of an approved MRI SPIO contrast agent injected into the tail vein of living mice has been demonstrated. However, nanoparticles are rapidly removed from the blood stream by the mononuclear phagocyte system. Therefore, imaging applications for long-term monitoring require the repeated administration of bolus injections, which complicates quantitative comparisons due to the temporal variations in concentration. Encapsulation of SPIOs into red blood cells (RBCs) has been suggested to increase the blood circulation time of nanoparticles. This work presents first evidence that SPIO-loaded RBCs can be imaged in the blood pool of mice several hours after injection using MPI. This finding is supported by magnetic particle spectroscopy performed to quantify the iron concentration in blood samples extracted from the mice 3 and 24 h after injection of SPIO-loaded RBCs. Based on these results, new MPI applications can be envisioned, such as permanent 3D real-time visualization of the vessel tree during interventional procedures, bleeding monitoring after stroke, or long-term monitoring and treatment control of cardiovascular diseases. (paper)

  20. Low-dose ECG-gated 64-slices helical CT angiography of the chest: evaluation of image quality in 105 patients

    International Nuclear Information System (INIS)

    D'Agostino, A.G.; Remy-Jardin, M.; Khalil, C.; Remy, J.; Delannoy-Deken, V.; Duhamel, A.; Flohr, T.

    2006-01-01

    The purpose of this study was to evaluate image quality of low-dose electrocardiogram (ECG)-gated multislice helical computed tomography (CT) angiograms of the chest. One hundred and five consecutive patients with a regular sinus rhythm (72 men; 33 women) underwent ECG-gated CT angiographic examination of the chest without administration of beta blockers using the following parameters: (a) collimation 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices, rotation time 0.33 s, pitch 0.3; (b) 120 kV, 200 mAs; (c) use of two dose modulation systems, including adjustment of the mAs setting to the patient's size and anatomical shape and an ECG-controlled tube current. Subjective and objective image quality was evaluated by two radiologists in consensus on 3-mm-thick scans reconstructed at 55% of the response rate (RR) interval. The population and protocol characteristics included: (a) a mean [±standard deviation (SD)] body mass index (BMI) of 24.47 (±4.64); (b) a mean (±SD) heart rate of 72.04 (±15.76) bpm; (c) a mean (±SD) scanning time of 18.3 (±2.73) s; (d) a mean (±SD) dose-length product (DLP) value of 260.57 (±83.67) mGy/cm; (e) an estimated average effective dose of 4.95 (±1.59) mSv. Subjective noise was depicted in a total of nine examinations (8.5%), always rated as mild. Objective noise was assessed by measuring the standard deviation of pixel values in a homogeneous region of interest within the trachea and descending aorta; SD was 15.91 HU in the trachea and 22.16 HU in the descending aorta, with no significant difference in the mean value of the standard deviations between the four categories of BMI except for obese patients, who had a higher mean SD within the aorta. Interpolation artefacts were depicted in 22 patients, with a mean heart rate significantly lower than that of patients without interpolation artifacts, rated as mild in 11 patients and severe in 11 patients. The severity of interpolation artefacts

  1. Bicuspid aortic valves: Diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, David J., E-mail: david.murphy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); McEvoy, Sinead H., E-mail: s.mcevoy@st-vincents.ie [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland); Iyengar, Sri, E-mail: sri.iyengar@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Feuchtner, Gudrun, E-mail: Gudrun.Feuchtner@i-med.ac.at [Department of Radiology, Innsbruck Medical University, Anichstr. 35, A-6020 Innsbruck (Austria); Cury, Ricardo C., E-mail: r.cury@baptisthealth.net [Department of Radiology, Baptist Cardiac and Vascular Institute, 8900 North Kendall Drive, Miami, FL 33176 (United States); Roobottom, Carl, E-mail: carl.roobottom@nhs.net [Department of Radiology, Plymouth Hospitals NHS Trust, Plymouth Devon PL6 8DH (United Kingdom); Plymouth University Peninsula Schools of Medicine and Dentistry (United Kingdom); Baumueller, Stephan, E-mail: Hatem.Alkadhi@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Alkadhi, Hatem, E-mail: stephan.baumueller@usz.ch [Institute for Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, CH-8091 Zurich (Switzerland); Dodd, Jonathan D., E-mail: jonniedodd@gmail.com [Department of Radiology, St Vincent' s University Hospital, Elm Park, Dublin 4 (Ireland)

    2014-08-15

    Objectives: To assess the diagnostic accuracy of standard axial 64-slice chest CT compared to aortic valve image plane ECG-gated cardiac CT for bicuspid aortic valves. Materials and methods: The standard axial chest CT scans of 20 patients with known bicuspid aortic valves were blindly, randomly analyzed for (i) the appearance of the valve cusps, (ii) the largest aortic sinus area, (iii) the longest aortic cusp length, (iv) the thickest aortic valve cusp and (v) valve calcification. A second blinded reader independently analyzed the appearance of the valve cusps. Forty-two age- and sex-matched patients with known tricuspid aortic valves were used as controls. Retrospectively ECG-gated cardiac CT multiphase reconstructions of the aortic valve were used as the gold-standard. Results: Fourteen (21%) scans were scored as unevaluable (7 bicuspid, 7 tricuspid). Of the remainder, there were 13 evaluable bicuspid valves, ten of which showed an aortic valve line sign, while the remaining three showed a normal Mercedes-Benz appearance owing to fused valve cusps. The 35 evaluable tricuspid aortic valves all showed a normal Mercedes-Benz appearance (P = 0.001). Kappa analysis = 0.62 indicating good interobserver agreement for the aortic valve cusp appearance. Aortic sinus areas, aortic cusp lengths and aortic cusp thicknesses of ≥3.8 cm{sup 2}, 3.2 cm and 1.6 mm respectively on standard axial chest CT best distinguished bicuspid from tricuspid aortic valves (P < 0.0001 for all). Of evaluable scans, the sensitivity, specificity, positive and negative predictive values of standard axial chest CT in diagnosing bicuspid aortic valves was 77% (CI 0.54–1.0), 100%, 100% and 70% respectively. Conclusion: The aortic valve is evaluable in approximately 80% of standard chest 64-slice CT scans. Bicuspid aortic valves may be diagnosed on evaluable scans with good diagnostic accuracy. An aortic valve line sign, enlarged aortic sinuses and elongated, thickened valve cusps are specific CT

  2. ECG-gated quiescent-interval single-shot MR angiography of the lower extremities: Initial experience at 3 T

    International Nuclear Information System (INIS)

    Knobloch, G.; Gielen, M.; Lauff, M.-T.; Romano, V.C.; Schmitt, P.; Rick, M.; Kröncke, T.J.; Huppertz, A.; Hamm, B.; Wagner, M.

    2014-01-01

    Aim: To evaluate the feasibility of unenhanced electrocardiography (ECG)-gated quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) of the lower extremities at 3 T. Materials and methods: Twenty-five patients with known or suspected peripheral arterial disease underwent ECG-gated QISS-MRA and contrast-enhanced MRA (CE-MRA) at 3 T. Two independent readers performed a per-segment evaluation of the MRA datasets. Image quality was rated on a four-point scale (1 = excellent to 4 = non-diagnostic; presented as medians with interquartile range). Diagnostic performance of QISS-MRA was evaluated using CE-MRA as the reference standard. Results: QISS-MRA and CE-MRA of all patients were considered for analysis, resulting in 807 evaluated vessel segments for each MRA technique. Readers 1 and 2 rated image quality of QISS-MRA as diagnostic in 97.3% and 97% of the vessel segments, respectively. CE-MRA was rated diagnostic in all vessel segments. Image quality of the proximal vessel segments, including the infrarenal aorta, iliac arteries, and common femoral artery, was significantly lower on QISS-MRA compared to CE-MRA [image quality score across readers: 2 (1,3) versus 1 (1,1) p < 0.001]. In the more distal vessel segments, image quality of QISS-MRA was excellent and showed no significant difference compared to CE-MRA [image quality score across readers: 1 (1,1) versus 1 (1,1) p = 0.036]. Diagnostic performance of QISS-MRA was as follows (across readers): sensitivity: 87.5% (95% CI: 80.2–92.4%); specificity: 96.1% (95% CI: 93.6–97.6%); diagnostic accuracy: 94.9% (95% CI: 92.6–96.5%). Conclusions: QISS-MRA of the lower extremities is feasible at 3 T and provides high image quality, especially in the distal vessel segments

  3. Evaluation of blood signal in cardiac MR imaging using ''black-blood'' technique

    International Nuclear Information System (INIS)

    Nakanishi, Tadashi; Yamada, Takayuki; Tamura, Akihisa; Miyasaka, Kenji; Kohata, Minako; Ono, Chiaki; Kajima, Toshio; Ito, Katsuhide

    1999-01-01

    Degradation of image quality encountered in cardiac imaging has been attributed to flowing blood signal in the ventricular cavity. To solve this problem, a sequence in which a pair of selective and non-selective inversion pulse in used for a preparation pulse, has been proposed. However, even with this sequence we frequently observed the signal in the blood pool caused by blood itself rather than blood flow. In this article, we investigated the characteristics of those signals. Five healthy normal volunteers and 13 patients with ischemic heart disease were scanned with a 1.5-tesla MR imager. Breath-hold ECG gated fast spin echo with the pair of inversion pulses was performed to obtain cardiac images with T 2 contrast. Typical blood signal appeared as inhomogeneous high intense band adjacent to inner surface of left ventricular apex. At ventricular base, no such signal was encountered even at akinetic myocardium in patients with old myocardial infarction. This signal was observed in all volunteers and 39% of patients. Decrease of TR resulting from tachycardia tended to reduce the blood signal in the left ventricular cavity. Thicker slice section and selective inversion pulse tended to increase the blood signal. Recognition of the signal is essential to differentiate true myocardial infarcts from blood signal, although bright blood imaging like gradient echo or thinner section can partly be helpful. (author)

  4. Diagnosis of accessory conduction pathway using ECG-gated emission CT analysis. Studies in patients with WPW syndrome who underwent surgery

    Energy Technology Data Exchange (ETDEWEB)

    Misaki, Takuro; Mukai, Keiichi; Tsubota, Makoto; Iwa, Takashi; Nakajima, Ken-ichi; Hisada, Kin-ichi

    1987-09-01

    Pinpointing the location of accessory conduction pathway (ACP) is of great importance in the surgical treatment for Wolff-Parkinson-White (WPW) syndrome. For this purpose, this study explored the usefulness of ECG-gated emission computed tomography (Gated-ECT) in 30 patients who preoperatively underwent Gated-ECT. The site of earliest contraction at level of atrioventicular valves, obtained on tomographic phase analysis, was compared with the site of earliest activation, obtained on epicardial mapping during surgery. The concordance rate of the two methods was 94 % (28/30). Among them, one patient was found to have the association of corrected transposition of great arteries on Gated-ECT. Gated-ECT was, however, of limited value in differentiating right posterior ACP from right postseptal ACP. The discordance between the sites of earliest contraction and activation, which was observed in the two others, was likely due to decreased wall motion resulting from myocardial disturbance. Gated-ECT may have a diagnostic potential for the location of ACP, especially in view of providing images that corresponded to the surgical anatomy. (Namekawa, K.).

  5. Safety and efficacy of a drug regimen to control heart rate during 64-slice ECG-gated coronary CTA in children

    International Nuclear Information System (INIS)

    Rigsby, Cynthia K.; Nicholas, Angela C.; deFreitas, R.A.; Leidecker, Christianne; Johanek, Andrew J.; Anley, Peter; Wang, Deli; Uejima, Tetsu

    2010-01-01

    The adult practice for ECG-gated single-source 64-slice coronary CTA (CCTA) includes administering beta-blockers to reduce heart rate. There are limited data on this process in children. To evaluate the safety and efficacy of a drug regimen to decrease heart rate before performing CCTA in children. IV remifentanil and esmolol infusion were chosen to decrease heart rate in 41 children (mean age 6.5 years) while they were under general anesthesia (GA) for CCTA. Drug doses, changes in heart rate and procedural complications were recorded. CCTA image quality was graded on a scale of 1 to 5. The relationships between image quality and heart rate and image quality and age were evaluated. Patient effective radiation doses were calculated. Heart rates were lowered utilizing esmolol (4 children), remifentanil (2 children) or both (35 children); 26 children received nitroglycerin for coronary vasodilation. The mean decrease in heart rate was 26%. There were no major complications. The average image-quality score was 4.4. Higher heart rates were associated with worse image quality (r = 0.67, P < 0.0001). Older age was associated with better image quality (r = 0.66, P < 0.0001). Effective radiation doses were 0.7 to 7.0 mSv. Heart rate reduction for pediatric CCTA can be safely and effectively achieved while yielding high-quality images. (orig.)

  6. Computer-based automated left atrium segmentation and volumetry from ECG-gated coronary CT angiography data. Comparison with manual slice segmentation and ultrasound planimetric methods

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, R.W.; Kraus, B.; Kerl, J.M.; Lehnert, T.; Vogl, T.J. [Universitaetsklinikum Frankfurt (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie; Bernhardt, D.; Vega-Higuera, F. [Siemens AG, Healthcare Sector, Forchheim (Germany). Computed Tomography; Ackermann, H. [Universitaetsklinikum Frankfurt (Germany). Inst. fuer Biostatistik und Mathematische Modellierung

    2010-12-15

    Purpose: Enlargement of the left atrium is a risk factor for cardiovascular or cerebrovascular events. We evaluated the performance of prototype software for fully automated segmentation and volumetry of the left atrium. Materials and Methods: In 34 retrospectively ECG-gated coronary CT angiography scans, the end-systolic (LAVsys) and end-diastolic (LAVdia) volume of the left atrium was calculated fully automatically by prototype software. Manual slice segmentation by two independent experienced radiologists served as the reference standard. Furthermore, two independent observers calculated the LAV utilizing two ultrasound planimetric methods ('area length' and 'prolate ellipse') on CTA images. Measurement periods were compared for all methods. Results: The left atrial volumes calculated with the prototype software were in excellent agreement with the results from manual slice segmentation (r = 0.97 - 0.99; p < 0.001; Bland-Altman) with excellent interobserver agreement between both radiologists (r = 0.99; p < 0.001). Ultrasound planimetric methods clearly showed a higher variation (r = 0.72 - 0.86) with moderate interobserver agreement (r = 0.51 - 0.79). The measurement period was significantly lower with the software (267 {+-} 28 sec; p < 0.001) than with ultrasound methods (431 {+-} 68 sec) or manual slice segmentation (567 {+-} 91 sec). Conclusion: The prototype software showed excellent agreement with manual slice segmentation with the least time consumption. This will facilitate the routine assessment of the LA volume from coronary CTA data and therefore risk stratification. (orig.)

  7. Assessment of automatic quantification of myocardial perfusion and left ventricular function derived from ECG gated myocardial SPECT with {sup 99m}Tc-tetrofosmin in ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Mitsunori; Habara, Hirokazu; Tatsuno, Hironari; Fukuda, Hiroshi; Hamada, Noriko; Kazatani, Yukio [Ehime Prefectural Central Hospital (Japan)

    1999-09-01

    Non-invasive assessment of ischemic heart disease (IHD) requires information of both myocardial perfusion and left ventricular (LV) function. Recently, automatic quantification of ECG-gated myocardial scintigraphy with {sup 99m}Tc-tetrofosmin (QGS) can provide both of them. QGS, coronary angiograms (CAG) and left venticulograms (LVG) were performed in 83 patients with severe IHD in same period. Significant stenosis of coronary artery in CAG were assessed by QGS. The sensitivity, specificity and accuracy of significant stenosis by QGS was excellent (85%, 93% and 88%). The LV end-distolic and end-systolic volumes (EDV and ESV), LV ejection fraction (EF) and regional LV wall motion determined by QGS were compared to LVG. There was a good correlation between the values obtained from QGS and LVG (EDV: r=0.86, ESV: r=0.94, EF: r=0.84, p<0.0001), but QGS tended to underestimate EDV and EF. High complete agreement of regional LV wall motion was gained with 427 (74.0%) out of total 581 segments. In conclusion, QGS data was considered to be useful for assessment of determine significant stenosis and LV function in severe IHD. (author)

  8. [Comparison of radiation dose reduction of prospective ECG-gated one beat scan using 320 area detector CT coronary angiography and prospective ECG-gated helical scan with high helical pitch (FlashScan) using 64 multidetector-row CT coronary angiography].

    Science.gov (United States)

    Matsutani, Hideyuki; Sano, Tomonari; Kondo, Takeshi; Fujimoto, Shinichiro; Sekine, Takako; Arai, Takehiro; Morita, Hitomi; Takase, Shinichi

    2010-12-20

    A high radiation dose associated with 64 multidetector-row computed tomography (64-MDCT) is a major concern for physicians and patients alike. A new 320 row area detector computed tomography (ADCT) can obtain a view of the entire heart with one rotation (0.35 s) without requiring the helical method. As such, ADCT is expected to reduce the radiation dose. We studied image quality and radiation dose of ADCT compared to that of 64-MDCT in patients with a low heart rate (HR≤60). Three hundred eighty-five consecutive patients underwent 64-MDCT and 379 patients, ADCT. Patients with an arrhythmia were excluded. Prospective ECG-gated helical scan with high HP (FlashScan) in 64 was used for MDCT and prospective ECG-gated conventional one beat scan, for 320-ADCT. Image quality was visually evaluated by an image quality score. Radiation dose was estimated by DLP (mGy・cm) for 64-MDCT and DLP.e (mGy・cm) for 320-ADCT. Radiation dose of 320-ADCT (208±48 mGy・cm) was significantly (P<0.0001) lower than that of 64-MDCT (484±112 mGy・cm), and image quality score of 320-ADCT (3.0±0.2) was significantly (P=0.0011) higher than that of 64-MDCT (2.9±0.4). Scan time of 320-ADCT (1.4±0.1 s) was also significantly (P<0.0001) shorter than that of 64-MDCT (6.8±0.6 s). 320-ADCT can achieve not only a reduction in radiation dose but also a superior image quality and shortening of scan time compared to 64-MDCT.

  9. Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

    Energy Technology Data Exchange (ETDEWEB)

    Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V. (Mt. Sinai Medical Center, New York, NY (USA))

    1989-09-01

    Blood-pool subtraction has been proposed to enhance {sup 111}In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging.

  10. Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

    International Nuclear Information System (INIS)

    Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V.

    1989-01-01

    Blood-pool subtraction has been proposed to enhance 111 In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging

  11. Slower lower limb blood pooling in young women with orthostatic intolerance.

    Science.gov (United States)

    Lindenberger, Marcus; Länne, Toste

    2015-01-01

    What is the central question of this study? Orthostatic stress is mostly caused by venous blood pooling in the lower limbs. Venous distension elicits sympathetic responses, and increased distension speed enhances the cardiovascular response. We examine whether lower limb blood pooling rate during lower body negative pressure is linked to orthostatic intolerance. What is the main finding and its importance? A similar amount of blood was pooled in the lower limb, but at a slower rate in women who developed signs of orthostatic intolerance. The difference in blood pooling rate increased with orthostatic stress and was most prominent at a presyncope-inducing level of lower body negative pressure. The findings have implications for the pathophysiology as well as treatment of orthostatic intolerance. Vasovagal syncope is common in young women, but its aetiology remains elusive. Orthostatic stress-induced lower limb blood pooling is linked with central hypovolaemia and baroreceptor unloading. Venous distension in the arm elicits a sympathetic response, which is enhanced with more rapid distension. Our aim was to study both the amount and the speed of lower limb pooling during orthostatic stress and its effects on compensatory mechanisms to maintain cardiovascular homeostasis in women with orthostatic intolerance. Twenty-seven healthy women, aged 20-27 years, were subjected to a lower body negative pressure (LBNP) of 11-44 mmHg. Five women developed symptoms of vasovagal syncope (orthostatic intolerant) and were compared with the remaining women, who tolerated LBNP well (orthostatic tolerant). Lower limb blood pooling, blood flow and compensatory mobilization of venous capacitance blood were measured. Lower body negative pressure induced equal lower limb blood pooling in both groups, but at a slower rate in orthostatic intolerant women (e.g. time to 50% of total blood pooling, orthostatic intolerant 44 ± 7 s and orthostatic tolerant 26 ± 2 s; P intolerant women (P = 0

  12. Quantitative evaluation of renal dynamic scan with 99mTc-MAG3 assessment of interoposterior myocardial infarction using ECG gated SPECT with 99mTc-MIBI

    International Nuclear Information System (INIS)

    Cho, Keiichi; Kumita, Shinichiro; Mizumura, Sunao

    1997-01-01

    Simultaneous assessment of regional myocardial perfusion and local contraction ability of interoposterior myocardial infarction was examined by ECG gated SPECT. In thirteen cases of acute interoposterior myocardial infarction, the above-mentioned data were obtained by 180deg data acquisition method using L-shaped 2 detecting element type gamma camera. Mean and standard deviation of %Uptake and wall thickening (WT) in inferior wall were as follows: Infarction case; 57±9.2%/23±11.3%, normal case; 71±8.2%/61±10.2%. The significant depression (p<0.01/p<0.001) of both data were found in the infarction case. The both data in posterior wall were as follows: Infarction case; 55±10.7%/16±8.9%, normal case; 64±9.7%/41±15.0%. The significant depression (p<0.05/p<0.001) were also found in the infarction case. In both inferior wall and posterior wall, the AUC of ROC curve of WT was greater than that of %Uptake, and diagnostic ability of this method was favorable. The best sensitivity/specificity rate and the threshold were as follows: %Uptake of inferior wall 77/65, -0.5SD, WT of inferior wall 100/100, -2SD, %Uptake of posterior wall 62/82, -1SD, WT of posterior wall 85/88, -4SD. Accordingly, in diagnosis of interoposterior myocardial infarction, assessment of focus cardiac function, for example WT, is necessary as well as %Uptake. (K.H.)

  13. Non-enhanced 3D MR angiography of the lower extremity using ECG-gated TSE imaging with non-selective refocusing pulses. Initial experience

    International Nuclear Information System (INIS)

    Lanzman, R.S.; Blondin, D.; Orzechowski, D.; Scherer, A.; Moedder, U.; Kroepil, P.; Godehardt, E.

    2010-01-01

    Purpose: To evaluate non-enhanced 3D MR angiography using turbo spin echo (TSE) imaging with non-selective refocusing pulses (NATIVE SPACE MRA) for the visualization of the arteries of the lower extremity. Materials and Methods: Three-station imaging (iliac arteries, femoral arteries, arteries of the lower leg) was performed in 8 healthy volunteers and 3 patients with peripheral artery disease (PAD) using a 1.5 T MR scanner. In 8 healthy volunteers, 4 different acquisition schemes were performed with the following imaging parameters: S 1: acquisition with every heartbeat (RR = 1), spoiler gradient of 25 % (SG = 25 %); S 2: RR = 1, SG = 0 %; S 3: RR = 2, SG = 25 %; S 4: RR = 2, SG = 0 %. The subjective image quality on a 4-point-scale (4 = excellent to 1 = not diagnostic) and relative SNR were assessed. In 3 patients with peripheral artery disease (PAD), SPACE MRA was performed for assessment of stenosis. Results: The mean subjective image quality was significantly lower for the iliac arteries compared to the femoral arteries and arteries of the lower leg (p < 0.0001). The subjective image quality for acquisition scheme S 1 was significantly lower than the image quality for S 3 and S 4 for the iliac arteries (p < 0.01), while the subjective image quality for acquisition scheme S 2 was significantly lower than S 3 and S 4 for the femoral arteries and the arteries of the lower leg (p < 0.01). The relative SNR was significantly higher for acquisition schemes S 3 and S 4 as compared to S 1 and S 2 (p < 0.0001) for all regions. SPACE MRA disclosed 7 significant stenoses in 3 PAD patients. Conclusion: ECG-gated SPACE MRA is a promising imaging technique for non-enhanced assessment of the arteries of the lower extremity. (orig.)

  14. Quantitative analysis of arterial flow properties for detection of non-calcified plaques in ECG-gated coronary CT angiography

    Science.gov (United States)

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

    2015-03-01

    We are developing a computer-aided detection system to assist radiologists in detection of non-calcified plaques (NCPs) in coronary CT angiograms (cCTA). In this study, we performed quantitative analysis of arterial flow properties in each vessel branch and extracted flow information to differentiate the presence and absence of stenosis in a vessel segment. Under rest conditions, blood flow in a single vessel branch was assumed to follow Poiseuille's law. For a uniform pressure distribution, two quantitative flow features, the normalized arterial compliance per unit length (Cu) and the normalized volumetric flow (Q) along the vessel centerline, were calculated based on the parabolic Poiseuille solution. The flow features were evaluated for a two-class classification task to differentiate NCP candidates obtained by prescreening as true NCPs and false positives (FPs) in cCTA. For evaluation, a data set of 83 cCTA scans was retrospectively collected from 83 patient files with IRB approval. A total of 118 NCPs were identified by experienced cardiothoracic radiologists. The correlation between the two flow features was 0.32. The discriminatory ability of the flow features evaluated as the area under the ROC curve (AUC) was 0.65 for Cu and 0.63 for Q in comparison with AUCs of 0.56-0.69 from our previous luminal features. With stepwise LDA feature selection, volumetric flow (Q) was selected in addition to three other luminal features. With FROC analysis, the test results indicated a reduction of the FP rates to 3.14, 1.98, and 1.32 FPs/scan at sensitivities of 90%, 80%, and 70%, respectively. The study indicated that quantitative blood flow analysis has the potential to provide useful features for the detection of NCPs in cCTA.

  15. Storage characteristics of multiple-donor pooled red blood cells compared to single-donor red blood cell units.

    Science.gov (United States)

    Mathur, Aabhas; Chowdhury, Raquibul; Hillyer, Christopher D; Mitchell, W Beau; Shaz, Beth H

    2016-12-01

    Each unit of blood donated is processed and stored individually resulting in variability in the amount of red blood cells (RBCs) collected, RBC properties, and the 24-hour posttransfusion RBC survivability. As a result, each unit differs in its ability to deliver oxygen and potentially its effects on the recipient. The goal of this study was to investigate the storage of pooled RBCs from multiple donors in comparison to control standard RBC units. Two units of irradiated, leukoreduced RBCs of same ABO, D, E, C, and K antigen phenotype were collected from each of five donors using apheresis. One unit from each donor was pooled in a 2-L bag and remaining units were used as controls. After being pooled, RBCs were separated in five bags and stored at 4°C along with the controls. Quality indexes were measured on Days 2, 14, and 28 for all the units. Adenosine triphosphate assays for both pooled and controls showed a slight decrease from Day 2 to Day 28 (pooled/control from 5.22/5.24 to 4.35/4.33 µmol/g hemoglobin [Hb]). 2,3-Diphosphoglycerate was successfully rejuvenated for all RBC units on Day 28 (pooled 11.46 µmol/g Hb; control 11.86 µmol/g Hb). The results showed a nonsignificant difference between pooled and control units, with a general trend of lower standard deviation for pooled units when compared to controls. Pooled units have reduced unit-to-unit variability. Future exploration of their immunogenicity is required before using pooled units for transfusion. © 2016 AABB.

  16. Magnetic resonance angiography with blood-pool contrast agents: future applications

    Energy Technology Data Exchange (ETDEWEB)

    Fink, C. [Univ. Hospitals, Grosshadern, Munich (Germany); Goyen, M. [Univ. Medical Center, Hamburg-Eppendorf, Hamburg (Germany); Lotz, J. [Hannover Medical School, Hannover (Germany)

    2007-03-15

    Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

  17. Magnetic resonance angiography with blood-pool contrast agents: future applications

    International Nuclear Information System (INIS)

    Fink, C.; Goyen, M.; Lotz, J.

    2007-01-01

    Blood pool agents remain in the intravascular space for a longer time period. Therefore the optimal imaging window for vascular structures is widened to about 30 minutes. Gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is the first blood-pool contrast agent approved in Europe for contrast-enhanced magnetic resonance angiography (MRA) of vessels in the abdomen, pelvis and lower extremity in adults. Other possible applications of blood-pool agents are now being considered, such as assessment of venous thromboembolism, coronary artery disease or sinus venous thrombosis. Perfusion MR imaging holds promise for detecting lung perfusion defects with higher spatial resolution and reduced scan time compared with radionuclide scintigraphy. In coronary artery disease, blood-pool agents enable a substantial increase in the quality of coronary artery imaging. Quantitative myocardial perfusion and myocardial viability seem to be possible, although modifications in protocols and sequence design are necessary for optimal results. Other novel applications of blood-pool agents include monitoring of inflammatory changes in systemic lupus erythematosus and evaluation of tumour invasion into lymph nodes and more reliable assessment of cerebral venous and sinus thrombosis. (orig.)

  18. Determination of left ventricular volume using gated blood pool tomography comparison with contrast ventriculography

    International Nuclear Information System (INIS)

    Lu Ping; Mo Lijun; Liu Xiujie

    1992-01-01

    48 patients with cardiac disease were studied with gated blood pool tomography to determine left ventricular volume at end diastole, end-systole and ejection fraction. The volumes were calculated from serial short-axis tomograms by multiplying the number of pixels and the known volume of each pixel. Excellent correlation was found between blood pool tomography and contrast ventriculographic volume. At end-diastole, r = 0.91 (P < 0.01); at end-systole, r = 0.95 (P < 0.01); for left ventricular ejection fraction, r 0.90 (P < 0.01). The results suggest that gated blood pool tomography is a promising noninvasive and direct method for measuring left ventricular volume

  19. /sup 99m/Tc dextran: a new blood-pool-labeling agent for radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Henze, E.; Robinson, G.D.; Kuhl, D.E.; Schelbert, H.R.

    1982-01-01

    We have explored the possibility of imaging the cardiac blood pool with dextran (Dx) labeled with /sup 99m/Tc (Tc) after Sn2+ reduction. Stannous dextran (SnDx) kits were prepared in advance and labeling was performed by adding /sup 99m/Tc. The labeling efficiency was greater than 95%. /sup 99m/Tc dextran (TcDx) was highly stable both in vivo and in vitro. In seven dogs we compared the quality of blood-pool images obtained with TcDx of different molecular weights (4 X 10(4) . Dx-40; 5 X 10(5) . Dx-500; 2 X 10(6) . Dx-2000) and with /sup 99m/Tc red blood cells (TcRBC) labeled in vitro, and determined the organ distribution of this new agent by whole-body scanning and blood sampling. TcDx provided high-quality cardiac blood-pool images up to 60 min after injection. The heart-to-lung ratios averaged 3.7 for TcDx-40, 3.9 for TcDx-500, and 5.4 for TcRBC at 60 min. Whereas TcDx-40 showed a relatively rapid initial urinary excretion and TcDx-2000 was degraded rapidly, TcDx-500 demonstrated the best kinetics for blood-pool imaging. Thus, TcDx is a new radiopharmaceutical with high labeling efficiency and stability. It overcomes a number of the limitations of currently used blood-labeling agents and may become useful for blood-pool imaging in man

  20. Prospective ECG-triggered axial CT at 140-kV tube voltage improves coronary in-stent restenosis visibility at a lower radiation dose compared with conventional retrospective ECG-gated helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, Jun; Fujioka, Chikako; Kiguchi, Masao; Kohno, Shingo [Hiroshima University Hospital, Department of Clinical Radiology, Hiroshima (Japan); Yamamoto, Hideya; Kitagawa, Toshiro [Hiroshima University, Department of Molecular and Internal Medicine, Division of Clinical Medical Science, Programs for Applied Biomedicine, Graduate School of Biomedical Sciences, Hiroshima (Japan); Ito, Katsuhide [Hiroshima University, Department of Radiology, Division of Medical Intelligence and Informatics, Programs for Applied Biomedicine, Graduate School of Biomedical Sciences, Hiroshima (Japan)

    2009-10-15

    The purpose of this study was to compare coronary 64-slice CT angiography (CTA) protocols, specifically prospective electrocardiograph (ECG)-triggered and retrospective ECG-gated CT acquisition performed using a tube voltage of 140 kV and 120 kV, regarding intracoronary stent imaging. Coronary artery stents (n=12) with artificial in-stent restenosis (50% luminal reduction, 40 HU) on a cardiac phantom were examined by CT at heart rates of 50-75 beats per minute (bpm). The subjective visibility of in-stent restenosis was evaluated with a three-point scale (1 clearly visible, 2 visible, and 3 not visible), and artificial lumen narrowing [(inner stent diameter - measured lumen diameter)/inner stent diameter], lumen attenuation increase ratio [(in-stent attenuation - coronary lumen attenuation)/coronary lumen attenuation], and signal-to-noise ratio of in-stent lumen were determined. The effective dose was estimated. The artificial lumen narrowing (mean 43%), the increase of lumen attenuation (mean 46%), and signal-to-noise ratio (mean 7.8) were not different between CT acquisitions (p=0.12-0.91). However, the visibility scores of in-stent restenosis were different (p<0.05) between ECG-gated CTA techniques: (a) 140-kV prospective (effective dose 4.6 mSv), 1.6; (b) 120-kV prospective (3.3 mSv), 1.8; (c) 140-kV retrospective (16.4-18.8 mSv), 1.9; and (d) 120-kV retrospective (11.0-13.4 mSv), 1.9. Thus, 140-kV prospective ECG-triggered CTA improves coronary in-stent restenosis visibility at a lower radiation dose compared with retrospective ECG-gated CTA. (orig.)

  1. Reliability analysis of visual ranking of coronary artery calcification on low-dose CT of the thorax for lung cancer screening: comparison with ECG-gated calcium scoring CT.

    Science.gov (United States)

    Kim, Yoon Kyung; Sung, Yon Mi; Cho, So Hyun; Park, Young Nam; Choi, Hye-Young

    2014-12-01

    Coronary artery calcification (CAC) is frequently detected on low-dose CT (LDCT) of the thorax. Concurrent assessment of CAC and lung cancer screening using LDCT is beneficial in terms of cost and radiation dose reduction. The aim of our study was to evaluate the reliability of visual ranking of positive CAC on LDCT compared to Agatston score (AS) on electrocardiogram (ECG)-gated calcium scoring CT. We studied 576 patients who were consecutively registered for health screening and undergoing both LDCT and ECG-gated calcium scoring CT. We excluded subjects with an AS of zero. The final study cohort included 117 patients with CAC (97 men; mean age, 53.4 ± 8.5). AS was used as the gold standard (mean score 166.0; range 0.4-3,719.3). Two board-certified radiologists and two radiology residents participated in an observer performance study. Visual ranking of CAC was performed according to four categories (1-10, 11-100, 101-400, and 401 or higher) for coronary artery disease risk stratification. Weighted kappa statistics were used to measure the degree of reliability on visual ranking of CAC on LDCT. The degree of reliability on visual ranking of CAC on LDCT compared to ECG-gated calcium scoring CT was excellent for board-certified radiologists and good for radiology residents. A high degree of association was observed with 71.6% of visual rankings in the same category as the Agatston category and 98.9% varying by no more than one category. Visual ranking of positive CAC on LDCT is reliable for predicting AS rank categorization.

  2. Thin-section CT of lung without ECG gating: 64-detector row CT can markedly reduce cardiac motion artifact which can simulate lung lesions

    International Nuclear Information System (INIS)

    Yanagawa, Masahiro; Tomiyama, Noriyuki; Sumikawa, Hiromitsu; Inoue, Atsuo; Daimon, Tadahisa; Honda, Osamu; Mihara, Naoki; Johkoh, Takeshi; Nakamura, Hironobu

    2009-01-01

    Purpose: Motion artifacts, which can mimic thickened bronchial wall and the cystic appearance of bronchiectasis, constitute a potential pitfall in the diagnosis of interstitial or bronchial disease. Therefore, purpose of our study was to evaluate whether 64-detector row CT (64-MDCT) enables a reduction in respiratory or cardiac motion artifacts in the lung area on thin-section CT without ECG gating, and to examine the correlation between cardiac motion artifact and heart rate. Materials and methods: Thirty-two patients with suspected diffuse lung disease, who underwent both 8- and 64-MDCT (gantry rotation time, 0.5 and 0.4 s, respectively), were included. The heart rates of an additional 155 patients were measured (range, 48-126 beats per minute; mean, 76 beats per minute) immediately prior to 64-MDCT, and compared to the degree of cardiac motion artifact. Two independent observers evaluated the following artifacts on a monitor without the knowledge of relevant clinical information: (1) artifacts on 8- and 64-MDCT images with 1.25-mm thickness and those on 64-MDCT images with 0.625-mm thickness in 32 patients; and (2) artifacts on 64-MDCT images with 0.625-mm thickness in 155 patients. Results: Interobserver agreement was good in evaluating artifacts on 8-MDCT images with 1.25-mm thickness (weighted Kappa test, κ = 0.61-0.71), and fair or poor in the other evaluations (κ < 0.31). Two observers stated that cardiac motion artifacts were more significant on 8-MDCT than on 64-MDCT in all 32 patients. Statistically significant differences were found at various checkpoints only in comparing artifacts between 8- and 64-MDCT for 1.25-mm thickness (Wilcoxon's signed-rank test, p < 0.0017). Cardiac motion artifacts on 64-MDCT had no significant correlation with heart rate (Spearman's correlation coefficient by rank test). Conclusion: The high temporal resolution of 64-MDCT appears to reduce cardiac motion artifact that can affect thin-section scans of the lung parenchyma

  3. Thin-section CT of lung without ECG gating: 64-detector row CT can markedly reduce cardiac motion artifact which can simulate lung lesions

    Energy Technology Data Exchange (ETDEWEB)

    Yanagawa, Masahiro [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan)], E-mail: m-yanagawa@radiol.med.osaka-u.ac.jp; Tomiyama, Noriyuki; Sumikawa, Hiromitsu; Inoue, Atsuo [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Daimon, Tadahisa [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Medicine, Division of Pulmonary Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498 (Japan); Honda, Osamu [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Mihara, Naoki [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Radiology, Osaka Advanced Medical Imaging Center, 5-20-1 Momoyamadai, Suita-city, Osaka 565-0854 (Japan); Johkoh, Takeshi [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Department of Medical Physics, Osaka University Graduate School of Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan); Nakamura, Hironobu [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita-city, Osaka 565-0871 (Japan)

    2009-01-15

    Purpose: Motion artifacts, which can mimic thickened bronchial wall and the cystic appearance of bronchiectasis, constitute a potential pitfall in the diagnosis of interstitial or bronchial disease. Therefore, purpose of our study was to evaluate whether 64-detector row CT (64-MDCT) enables a reduction in respiratory or cardiac motion artifacts in the lung area on thin-section CT without ECG gating, and to examine the correlation between cardiac motion artifact and heart rate. Materials and methods: Thirty-two patients with suspected diffuse lung disease, who underwent both 8- and 64-MDCT (gantry rotation time, 0.5 and 0.4 s, respectively), were included. The heart rates of an additional 155 patients were measured (range, 48-126 beats per minute; mean, 76 beats per minute) immediately prior to 64-MDCT, and compared to the degree of cardiac motion artifact. Two independent observers evaluated the following artifacts on a monitor without the knowledge of relevant clinical information: (1) artifacts on 8- and 64-MDCT images with 1.25-mm thickness and those on 64-MDCT images with 0.625-mm thickness in 32 patients; and (2) artifacts on 64-MDCT images with 0.625-mm thickness in 155 patients. Results: Interobserver agreement was good in evaluating artifacts on 8-MDCT images with 1.25-mm thickness (weighted Kappa test, {kappa} = 0.61-0.71), and fair or poor in the other evaluations ({kappa} < 0.31). Two observers stated that cardiac motion artifacts were more significant on 8-MDCT than on 64-MDCT in all 32 patients. Statistically significant differences were found at various checkpoints only in comparing artifacts between 8- and 64-MDCT for 1.25-mm thickness (Wilcoxon's signed-rank test, p < 0.0017). Cardiac motion artifacts on 64-MDCT had no significant correlation with heart rate (Spearman's correlation coefficient by rank test). Conclusion: The high temporal resolution of 64-MDCT appears to reduce cardiac motion artifact that can affect thin-section scans of

  4. Use of blood-pool imaging in evaluation of diffuse activity patterns in technetium-99m pyrophosphate myocardial scintigraphy.

    Science.gov (United States)

    Cowley, M J; Mantle, J A; Rogers, W J; Russell, R O; Rackley, C E; Logic, J R

    1979-06-01

    It has been suggested that diffuse Tc-99m pyrophosphate precordial activity may be due to persistent blood-pool activity in routine delayed views during myocardial imaging. To answer this question, we reviewed myocardial scintigrams recorded 60--90 min following the injection of 12--15 mCi of Tc-99m pyrophosphate for the presence of diffuse precordial activity, and compared these with early images of the blood pool in 265 patients. Diffuse activity in the delayed images was identified in 48 patients: in 20 with acute myocardial infarction and in 28 with no evidence of it. Comparison of these routine delayed images with early views of the blood pool revealed two types of patterns. In patients with acute infarction, 95% had delayed images that were distinguishable from blood pool either because the activity was smaller than the early blood pool, or by the presence of localized activity superimposed on diffuse activity identical to blood pool. In those without infarction, 93% had activity distribution in routine delayed views matching that in the early blood-pool images. The usefulness of the diffuse TcPPi precordial activity in myocardial infarction is improved when early blood-pool imaging is used to exclude persistence of blood-pool activity as its cause. Moreover, it does not require additional amounts of radioactivity nor complex computer processing, a feature that may be of value in the community hospital using the technique to "rule out" infarction 24--72 hr after onset of suggestive symptoms.

  5. Use of blood-pool imaging in evaluation of diffuse activity patterns in technetium-99m pyrophosphate myocardial scintigraphy

    International Nuclear Information System (INIS)

    Cowley, M.J.; Mantle, J.A.; Rogers, W.J.; Russell, R.O. Jr.; Rackley, C.E.; Logic, J.R.

    1979-01-01

    It has been suggested that diffuse 99m Tc pyrophosphate precordial activity may be due to persistent blood-pool activity in routine delayed views during myocardial imaging. To answer this question, we reviewed myocardial scintigrams recorded 60 to 90 min following the injection of 12 to 15 mCi of 99m Tc pyrophosphate for the presence of diffuse precordial activity, and compared these with early images of the blood pool in 265 patients. Diffuse activity in the delayed images was identified in 48 patients: in 20 with acute myocardial infarction and in 28 with no evidence of it. Comparison of these routine delayed images with early views of the blood pool revealed two types of patterns. In patients with acute infarction, 95% had delayed images that were distinguishable from blood pool either because the activity was smaller than the early blood pool, or by the presence of localized activity superimposed on diffuse activity identical to blood pool. In those without infarction, 93% had activity distribution in routine delayed views matching that in the early blood-pool images. The usefulness of the diffuse TcPPi precordial activity in myocardial infarction is improved when early blood-pool imaging is used to exclude persistence of blood-pool activity as its cause. Moreover, it does not require additional amounts of radioactivity nor complex computer processing, a feature that may be of value in the community hospital using the technique to rule out infarction 24 to 72 hr after onset of suggestive symptoms

  6. 18F-FDG-labeled red blood cell PET for blood-pool imaging: preclinical evaluation in rats.

    Science.gov (United States)

    Matsusaka, Yohji; Nakahara, Tadaki; Takahashi, Kazuhiro; Iwabuchi, Yu; Nishime, Chiyoko; Kajimura, Mayumi; Jinzaki, Masahiro

    2017-12-01

    Red blood cells (RBCs) labeled with single-photon emitters have been clinically used for blood-pool imaging. Although some PET tracers have been introduced for blood-pool imaging, they have not yet been widely used. The present study investigated the feasibility of labeling RBCs with 18 F-2-deoxy-2-fluoro-D-glucose ( 18 F-FDG) for blood-pool imaging with PET. RBCs isolated from venous blood of rats were washed with glucose-free phosphate-buffered saline and labeled with 18 F-FDG. To optimize labeling efficiency, the effects of glucose deprivation time and incubation (labeling) time with 18 F-FDG were investigated. Post-labeling stability was assessed by calculating the release fraction of radioactivity and identifying the chemical forms of 18 F in the released and intracellular components of 18 F-FDG-labeled RBCs incubated in plasma. Just after intravenous injection of the optimized autologous 18 F-FDG-labeled RBCs, dynamic PET scans were performed to evaluate in vivo imaging in normal rats and intraabdominal bleeding models (temporary and persistent bleeding). The optimal durations of glucose deprivation and incubation (labeling) with 18 F-FDG were 60 and 30 min, respectively. As low as 10% of 18 F was released as the form of 18 F-FDG from 18 F-FDG-labeled RBCs after a 60-min incubation. Dynamic PET images of normal rats showed strong persistence in the cardiovascular system for at least 120 min. In the intraabdominal bleeding models, 18 F-FDG-labeled RBC PET visualized the extravascular blood clearly and revealed the dynamic changes of the extravascular radioactivity in the temporary and persistent bleeding. RBCs can be effectively labeled with 18 F-FDG and used for blood-pool imaging with PET in rats.

  7. Phase analysis in gated blood pool tomography. Detection of accessory conduction pathway

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Kenichi; Bunko, Hisashi; Tada, Akira; Taki, Junichi; Nanbu, Ichiro (Kanazawa Univ. (Japan). School of Medicine)

    1984-02-01

    Phase analysis of gated blood pool study has been applied to detect the site of accessory conduction pathway (ACP) in the Wolff-Parkinson-White (WPW) syndrome; however, there was a limitation to detect the precise location of ACP by phase analysis alone. In this study, we applied phase analysis to gated blood pool tomography using seven pin hole tomography (7PT) and gated emission computed tomography (GECT) in 21 patients with WPW syndrome and 3 normal subjects. In 17 patients, the sites of ACPs were confirmed by epicardial mapping and the result of the surgical division of ACP. In 7PT, the site of ACP grossly agreed to the abnormal initial phase in phase image in 5 out of 6 patients with left cardiac type. In GECT, phase images were generated in short axial, vertical and horizontal long axial sections. In 8 out of 9 patients, the site of ACP was correctly identified by phase images, and in a patient who had two ACPs, initial phase corresponded to one of the two locations. Phase analysis of gated blood pool tomography has advantages for avoiding overlap of blood pools and for estimating three-dimensional propagation of the contraction, and can be a good adjunctive method in patients with WPW syndrome.

  8. Scintigraphic detection of gynaecological tumours by sup(99m)Tc-HSA blood pool imaging

    Energy Technology Data Exchange (ETDEWEB)

    Georgiou, E C; Arkas, A Z; Alevizaki, C C; Gnafakis, N [Evangelismos Hospital, Athens (Greece). Dept. of Endocrinology and Radioisotopes; Evangelismos Hospital, Athens (Greece). Gynaecology Clinic)

    1979-12-01

    Three cases of scintigraphic visualization of gynaecological tumours by sup(99m)Tc-HSA blood pool imaging are presented, i.e. one case of fibrothecoma ('cold' area visualization) and two cases of fibromyoma ('hot' area visualization). It is suggested that this technique may be useful in the preoperative evaluation of gynaecological tumours and their vascularity.

  9. Three-dimensional magnetic resonance coronary angiography using a new blood pool contrast agent : Initial experience

    NARCIS (Netherlands)

    Bedaux, WLF; Hofman, MBM; Wielopolski, PA; de Cock, CC; Hoffmann, [No Value; Oudkerk, M; de Feyter, PJ; van Rossum, AC

    2002-01-01

    Objective: The aim of this feasibility study was to assess the effect of a new blood pool contrast agent on magnetic resonance coronary angiography (MRCA) in patients suspected of having coronary artery disease. Methods: Nine patients referred for diagnostic x-ray coronary, angiography in the

  10. Effect of solvent/detergent-treated pooled plasma on fibrinolysis in reconstituted whole blood.

    Science.gov (United States)

    Saadah, Nicholas H; van der Meer, Pieter F; Brinkman, Herm Jan M; de Korte, Dirk; Bontekoe, Ido J; Korsten, Herbert H; Middelburg, Rutger A; van der Bom, Johanna G; Schipperus, Martin R

    2017-10-01

    Hyperfibrinolysis has been observed in patients heavily transfused with solvent/detergent-treated pooled plasma (S/D plasma). We compared coagulation and fibrinolytic variables in blood containing S/D plasma with blood containing fresh-frozen plasma (FFP), with and without α2-antiplasmin or tranexamic acid (TXA) supplementation. Whole blood samples were reconstituted from red blood cells, platelet (PLT) concentrates, and varying mixtures of FFP and S/D plasma. Hematocrit and PLT count of reconstituted whole blood samples were varied. For a subset of runs, α2-antiplasmin or TXA was added to S/D plasma whole blood samples. Thromboelastography (TEG) analysis was performed to assess 50% clot lysis time (CLT 50% ), maximum amplitude (MA), and initial clotting time (R-time). The change in CLT 50% of whole blood as the plasma compartment transitions from FFP to S/D plasma was -52% (95% confidence interval [CI], -60% to -45%; p plasma in whole blood. α2-Antiplasmin and TXA restored clot lysis time in S/D plasma whole blood. Whole blood with S/D plasma has shorter clot lysis times in vitro compared to whole blood with FFP. α2-Antiplasmin and TXA restore clot lysis time of S/D plasma whole blood to that of FFP whole blood. Clinicians should be aware of the decreased clot lysis time associated with S/D plasma transfusion. © 2017 AABB.

  11. Non-enhanced ECG-gated respiratory-triggered 3-D steady-state free-precession MR angiography with slab-selective inversion: initial experience in visualisation of renal arteries in free-breathing children without renal artery abnormality

    International Nuclear Information System (INIS)

    Klee, Dirk; Lanzman, Rotem Shlomo; Blondin, Dirk; Antoch, Gerald; Schaper, Joerg; Schmitt, Peter; Oh, Jun; Salgin, Burak; Mayatepek, Ertan

    2012-01-01

    ECG-gated non-enhanced balanced steady-state free precession (bSSFP) MR angiography requires neither breath-holding nor administration of contrast material. To investigate the image quality of free-breathing ECG-gated non-enhanced bSSFP MR angiography of renal arteries in children. Fourteen boys and seven girls (mean age, 9.7 years; range, 7 weeks-17 years) with no history of renovascular disease were included. MRI was performed at 1.5 T. Subjective image quality of axial and coronal maximum-intensity-projection reconstructions of four segments (I, aorta and renal artery ostium; II, main renal artery; III, segmental branches; IV, intrarenal vessels) was evaluated using a 4-point scale (4 = excellent, 3 = good, 2 = acceptable, 1 = non-diagnostic). Image quality was excellent for segments I (mean ± SD, 3.9 ± 0.3) and II (4.0 ± 0.1), good for segment III (3.4 ± 0.9) and acceptable for segment IV (2.3 ± 1.1). Mean image quality did not differ between sedated and non-sedated children. bSSFP MR angiography enables visualisation of renal arteries in children. (orig.)

  12. Abdominal blood pool scintigraphy in the management of acute or intermittent gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Kalff, V.; Kelly, M.J.; Dudley, F.; Metz, G.

    1983-01-01

    Gastrointestinal blood pool scintigraphy, using a modified in-vivo blood cell labelling technique with technetium-99, is a new, easily performed, non-invasive procedure. It is valuable in screening patients with acute or intermittent gastrointestinal blood loss in whom duodenoscopic and sigmoidoscopic findings are unhelpful. This paper reviews the value of this scintigraphic technique over the first eight months of its use in a major teaching hospital, and compares the results with other published data. If used and interpreted appropriately, scintigraphy is sensitive in detecting and localizing the bleeding site, and is very helpful in indicating the optimal timing of emergency contrast angiography

  13. Erroneous cardiac ECG-gated PET list-mode trigger events can be retrospectively identified and replaced by an offline reprocessing approach: first results in rodents

    International Nuclear Information System (INIS)

    Böning, Guido; Todica, Andrei; Vai, Alessandro; Lehner, Sebastian; Xiong, Guoming; Mille, Erik; Ilhan, Harun; Fougère, Christian la; Bartenstein, Peter; Hacker, Marcus

    2013-01-01

    The assessment of left ventricular function, wall motion and myocardial viability using electrocardiogram (ECG)-gated [ 18 F]-FDG positron emission tomography (PET) is widely accepted in human and in preclinical small animal studies. The nonterminal and noninvasive approach permits repeated in vivo evaluations of the same animal, facilitating the assessment of temporal changes in disease or therapy response. Although well established, gated small animal PET studies can contain erroneous gating information, which may yield to blurred images and false estimation of functional parameters. In this work, we present quantitative and visual quality control (QC) methods to evaluate the accuracy of trigger events in PET list-mode and physiological data. Left ventricular functional analysis is performed to quantify the effect of gating errors on the end-systolic and end-diastolic volumes, and on the ejection fraction (EF). We aim to recover the cardiac functional parameters by the application of the commonly established heart rate filter approach using fixed ranges based on a standardized population. In addition, we propose a fully reprocessing approach which retrospectively replaces the gating information of the PET list-mode file with appropriate list-mode decoding and encoding software. The signal of a simultaneously acquired ECG is processed using standard MATLAB vector functions, which can be individually adapted to reliably detect the R-peaks. Finally, the new trigger events are inserted into the PET list-mode file. A population of 30 mice with various health statuses was analyzed and standard cardiac parameters such as mean heart rate (119 ms ± 11.8 ms) and mean heart rate variability (1.7 ms ± 3.4 ms) derived. These standard parameter ranges were taken into account in the QC methods to select a group of nine optimal gated and a group of eight sub-optimal gated [ 18 F]-FDG PET scans of mice from our archive. From the list-mode files of the optimal gated group

  14. Study on 99Tcm-DTPA-HSA as a new blood pool scanning agent

    International Nuclear Information System (INIS)

    Liu Yunzhong; Zhang Zheng; Wu Qingwen

    1994-01-01

    The biological behavior of 99 Tc m -DTPA-HSA, 99 Tc m -RBC(in vivo) and 99 Tc m -HSA are studied in rabbits. Excellent cardiac blood-pool images are obtained by 99 Tc m -DTPT-HSA and 99 Tc m -RBC. Biodistribution studies show that 99 Tc m -DTPA-HSA has less accumulation than 99 Tc m -RBC in lungs and liver. They have similar count ratio of the cardiac blood pool to whole body. Ratio of heart/liver is 0.85 for 99 Tc m -DTPA-HSA, 0.95 for 99 Tc m -RBC and 0.62 for 99 Tc m -HSA. 99 Tc m -DTPA-HSA is a promising agent. It is readily performed only by single in vivo injection

  15. Diagnosis of Popliteal Venous Entrapment Syndrome by Magnetic Resonance Imaging Using Blood-Pool Contrast Agents

    International Nuclear Information System (INIS)

    Beitzke, Dietrich; Wolf, Florian; Juelg, Gregor; Lammer, Johannes; Loewe, Christian

    2011-01-01

    Popliteal vascular entrapment syndrome is caused by aberrations or hypertrophy of the gastrocnemius muscles, which compress the neurovascular structures of the popliteal fossa, leading to symptoms of vascular and degeneration as well as aneurysm formation. Imaging of popliteal vascular entrapment may be performed with ultrasound, magnetic resonance imaging (MRI), computed tomography angiography, and conventional angiography. The use of blood-pool contrast agents in MRI when popliteal vascular entrapment is suspected offers the possibility to perform vascular imaging with first-pass magnetic resonance angiographic, high-resolution, steady-state imaging and allows functional tests all within one examination with a single dose of contrast agent. We present imaging findings in a case of symptomatic popliteal vein entrapment diagnosed by the use of blood pool contrast-enhanced MRI.

  16. Ventricular function during the acute rejection of heterotopic transplanted heart: Gated blood pool studies

    International Nuclear Information System (INIS)

    Valette, H.; Bourguignon, M.H.; Desruennes, M.; Merlet, P.; Le Guludec, D.; Syrota, A.

    1991-01-01

    Twenty patients who had undergone a heterotopic heart transplant were studied prospectively to determine the relationship between rejection and ventricular dysfunction assessed from gated blood pool studies. A fully automated method for detecting ventricular edges was implemented; its success rate for the grafted left and right ventricles was 94% and 77%, respectively. The parameters, peak ejection and filling rates, were calculated pixel per pixel using a two-harmonic Fourier algorithm and then averaged over the ventricular region of interest. Peak filling and ejection rates were closely related with the severity of the rejection, while the left ventricular ejection fraction was not. Peak filling rates of both ventricles were the indices closely related to the presence of moderate rejection. Despite the low number of patients, these data suggested that gated blood pool derived indices of ventricular function are associated with ventricular dysfunction resulting from myocarditis rejection. Radionuclide ventriculography provides parametric data which are accurate and reliable for the diagnosis of rejection. (orig.)

  17. Cardiac tumours: non invasive detection and assessment by gated cardiac blood pool radionuclide imaging

    International Nuclear Information System (INIS)

    Pitcher, D.; Wainwright, R.; Brennand-Roper, D.; Deverall, P.; Sowton, E.; Maisey, M.

    1980-01-01

    Four patients with cardiac tumours were investigated by gated cardiac blood pool radionuclide imaging and echocardiography. Contrast angiocardiography was performed in three of the cases. Two left atrial tumours were detected by all three techniques. In one of these cases echocardiography alone showed additional mitral valve stenosis, but isotope imaging indicated tumour size more accurately. A large septal mass was detected by all three methods. In this patient echocardiography showed evidence of left ventricular outflow obstruction, confirmed at cardiac catheterisation, but gated isotope imaging provided a more detailed assessment of the abnormal cardiac anatomy. In the fourth case gated isotope imaging detected a large right ventricular tumour which had not been identified by echocardiography. Gated cardiac blood pool isotope imaging is a complementary technique to echocardiography for the non-invasive detection and assessment of cardiac tumours. (author)

  18. Value of lateral blood pool imaging in patients with suspected stress fractures of the tibia.

    Science.gov (United States)

    Mohan, Hosahalli K; Clarke, Susan E M; Centenara, Martin; Lucarelli, Amanda; Baron, Daniel; Fogelman, Ignac

    2011-03-01

    To critically evaluate the use of lateral blood pool imaging in athletes with lower limb pain and with a clinical suspicion of stress fracture. Two experienced nuclear medicine physicians evaluated 3-phase bone scans using 99mTc-methylene diphosphonate performed in 50 consecutive patients referred from a specialist sports injury clinic for suspected tibial stress fracture. The vascularity to the tibia as seen on the blood pool (second phase) images in the anterior/posterior views was compared with the lateral/medial view assessments. Stress fractures were presumed to be present when on the delayed images (third phase) there was a focal or fusiform area of increased tracer uptake involving the tibial cortex. Shin splints which are a recognized cause of lower limb pain in athletes mimicking stress fracture were diagnosed if increased tracer uptake was seen extending along the posterior tibial surface with no significant focal or fusiform area of uptake within this. Inter-reviewer agreement for the assessment of vascularity was also assessed using Cohen's Kappa scores. Twenty-four stress fractures in 24 patients and 66 shin splints in 40 patients were diagnosed. In 18 patients stress fracture and shin splints coexisted. In 10 patients no tibial pathology was identified. Of the 24 patients diagnosed with stress fractures, lateral/medial blood pool imaging was superior in the assessment of blood pool activity (P tibial stress fractures, lateral views of the tibia provide the optimal method for evaluation of vascularity. Prospective studies with quantitative or semi-quantitative assessment of skeletal vascularity could provide supplementary information relating to the pathophysiology of stress fractures, for example, the time scale of vascular changes after a tibial stress fracture, and potentially could have clinical relevance as to the assessment of the severity of stress fractures and their prognosis.

  19. Combined blood pool and extracellular contrast agents for pediatric and young adult cardiovascular magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Joyce T. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Robinson, Joshua D. [Ann and Robert Lurie Children' s Hospital of Chicago, Division of Pediatric Cardiology, 225 E. Chicago Ave., Box 21, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Deng, Jie [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Rigsby, Cynthia K. [Ann and Robert Lurie Children' s Hospital of Chicago, Department of Pediatrics, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Ann and Robert Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States)

    2016-12-15

    A comprehensive cardiac magnetic resonance (cardiac MR) study including both late gadolinium enhancement (LGE) and MR angiography may be indicated for patients with a history of acquired or congenital heart disease. To study the novel use of an extracellular agent for assessment of LGE combined with a blood pool contrast agent for detailed MR angiography evaluation to yield a comprehensive cardiac MR study in these patients. We reviewed clinical cardiac MR studies utilizing extracellular and blood pool contrast agents and noted demographics, clinical data and adverse events. We rated LGE image quality and MR angiography image quality for each vascular segment and calculated inter-rater variability. We also quantified contrast-to-noise ratio (CNR). Thirty-three patients (mean age 13.9 ± 3 years) received an extracellular contrast agent (10 gadobenate dimeglumine, 23 gadopentetate dimeglumine) and blood pool contrast agent (33 gadofosveset trisodium). No adverse events were reported. MRI indications included Kawasaki disease (8), cardiomyopathy and coronary anatomy (15), repaired congenital heart disease (8), and other (2). Mean LGE quality was 2.6 ± 0.6 with 97% diagnostic imaging. LGE quality did not vary by type of contrast agent given (P = 0.07). Mean MR angiography quality score was 4.7 ± 0.6, with high inter-rater agreement (k = 0.6-0.8, P < 0.002). MR angiography quality did not vary by type of contrast agent used (P = 0.6). Cardiac MR studies utilizing both extracellular and blood pool contrast agents are feasible and safe and provide excellent-quality LGE and MR angiography images. The use of two contrast agents allows for a comprehensive assessment of both myocardial viability and vascular anatomy during the same exam. (orig.)

  20. Combined blood pool and extracellular contrast agents for pediatric and young adult cardiovascular magnetic resonance imaging

    International Nuclear Information System (INIS)

    Johnson, Joyce T.; Robinson, Joshua D.; Deng, Jie; Rigsby, Cynthia K.

    2016-01-01

    A comprehensive cardiac magnetic resonance (cardiac MR) study including both late gadolinium enhancement (LGE) and MR angiography may be indicated for patients with a history of acquired or congenital heart disease. To study the novel use of an extracellular agent for assessment of LGE combined with a blood pool contrast agent for detailed MR angiography evaluation to yield a comprehensive cardiac MR study in these patients. We reviewed clinical cardiac MR studies utilizing extracellular and blood pool contrast agents and noted demographics, clinical data and adverse events. We rated LGE image quality and MR angiography image quality for each vascular segment and calculated inter-rater variability. We also quantified contrast-to-noise ratio (CNR). Thirty-three patients (mean age 13.9 ± 3 years) received an extracellular contrast agent (10 gadobenate dimeglumine, 23 gadopentetate dimeglumine) and blood pool contrast agent (33 gadofosveset trisodium). No adverse events were reported. MRI indications included Kawasaki disease (8), cardiomyopathy and coronary anatomy (15), repaired congenital heart disease (8), and other (2). Mean LGE quality was 2.6 ± 0.6 with 97% diagnostic imaging. LGE quality did not vary by type of contrast agent given (P = 0.07). Mean MR angiography quality score was 4.7 ± 0.6, with high inter-rater agreement (k = 0.6-0.8, P < 0.002). MR angiography quality did not vary by type of contrast agent used (P = 0.6). Cardiac MR studies utilizing both extracellular and blood pool contrast agents are feasible and safe and provide excellent-quality LGE and MR angiography images. The use of two contrast agents allows for a comprehensive assessment of both myocardial viability and vascular anatomy during the same exam. (orig.)

  1. The gated blood pool scan in the evaluation of coronary artery disease

    International Nuclear Information System (INIS)

    Anger, K.; Erbel, R.; Krebs, W.; Meyer, J.; Moeller, T.; Schweizer, P.; Yalkinoglu, O.; Technische Hochschule Aachen

    1983-01-01

    38 patients with clinically suspected coronary artery disease were studied by contrast ventriculography, 2-dimensional echocardiography and multiple gated blood pool imaging (MUGA) without stress. The results were compared with eath other and with the final diagnosis confirmed by coronary angiography. The left ventricular ejection fraction is evaluated nearly identically and with sufficient accuracy by both non-invasive methods, local motion abnormalities are on the other hand diagnosed in the best way by MUGA imaging in our own cases. (orig.) [de

  2. Evaluation of supine and sitting cardiac blood pool scans with sup(99m)Tc-HSA

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Kuwajima, Akira; Hisada, Kinichi

    1977-01-01

    In the differential diagnosis of enlarged cardiac silhouette on plain chest x-ray film, cardiac blood pool scan was usually performed at first. However, small amount of pericardial effusion was difficult to detect on cardiac blood pool scan and differentiation of pericardial effusion from myocardial thickening was sometimes difficult. We evaluated cardiac blood pool scan with sup(99m)Tc-HSA(human serum albumin) and gamma camera imaged on both supine and sitting position, and evaluated diagnostic efficiency of criteria for pericardial effusion of these scans. Fifty-seven patients suspected of having pericardial effusion were included in the study. Sixteen of these patients had pericardial effusion and 2 of these 16 patients had free pleural effusion. Three patients had pleural effusion alone and excluded from the study. Of the five criteria for pericardial effusion, separation between heart and right lung activities was most frequent in both effusion (true positive, TP=100% on both supine and sitting) and no effusion (false positive, FP=18.4% on supine and 23.7% on sitting) groups. However, increased heart and right lung separation on sitting position was rather frequent in effusion group, and this finding was also thought to be typical for effusion but not for myocardial thickening. Decreased cardiohepatic separation on sitting position was frequent in no effusion group, and FP rate was decreased from 18.4% (supine) to 10.5% (sitting). Two patients with both pericardial effusion and free pleural effusion were easily diagnosed on sitting cardiac blood pool scan. With ROC(receiver operating characteristic) curve, three criteria should be agreed on either supine or sitting scan for diagnosis of pericardial effusion, and six criteria should be agreed when both supine and sitting scans were employed for diagnosis of pericardial effusion. (auth.)

  3. Gated blood pool study in one case of endocarditis parietalis fibroplastica LOEFFLER - a case report

    Energy Technology Data Exchange (ETDEWEB)

    Feistel, H; Mahlstedt, J; Wolf, F

    1983-10-01

    The rare case of endocarditis parietalis fibroplastica Loeffler is described. In laevocardiography this kind of endomyocardfibrose, in our patient combined with excessive blood eosinophilia of 86%, presents a typical diastolic-systolic contraction pattern. Gated blood pool study matches well with the results of contrast angiography. Exercise-testing provoked an EF increase of from 48% to 55%, excluding CAD. Clinical complaints are not specific, caused by extreme restriction of myocardial compliance with high left ventricular filling pressure and subsequent mean pulmonary hypertonus. The patient died before the operative intervention in sudden heart death.

  4. Gated blood pool study in one case of endocarditis parietalis fibroplastica LOEFFLER - a case report

    International Nuclear Information System (INIS)

    Feistel, H.; Mahlstedt, J.; Wolf, F.

    1983-01-01

    The rare case of endocarditis parietalis fibroplastica Loeffler is described. In laevocardiography this kind of endomyocardfibrose, in our patient combined with excessive blood eosinophilia of 86%, presents a typical diastolic-systolic kontraction pattern. Gated blood pool study matches well with the results of contrast angiography. Exercise-testing provoked an EF increase of from 48% to 55%, excluding CAD. Clinical complaints are not specific, caused by extreme restriction of myocardial compliance with high left ventricular filling pressure and subsequent mean pulmonary hypertonus. The patient died before the operative intervention in sudden heart death. (orig.) [de

  5. Automatic localization of the left ventricular blood pool centroid in short axis cardiac cine MR images.

    Science.gov (United States)

    Tan, Li Kuo; Liew, Yih Miin; Lim, Einly; Abdul Aziz, Yang Faridah; Chee, Kok Han; McLaughlin, Robert A

    2018-06-01

    In this paper, we develop and validate an open source, fully automatic algorithm to localize the left ventricular (LV) blood pool centroid in short axis cardiac cine MR images, enabling follow-on automated LV segmentation algorithms. The algorithm comprises four steps: (i) quantify motion to determine an initial region of interest surrounding the heart, (ii) identify potential 2D objects of interest using an intensity-based segmentation, (iii) assess contraction/expansion, circularity, and proximity to lung tissue to score all objects of interest in terms of their likelihood of constituting part of the LV, and (iv) aggregate the objects into connected groups and construct the final LV blood pool volume and centroid. This algorithm was tested against 1140 datasets from the Kaggle Second Annual Data Science Bowl, as well as 45 datasets from the STACOM 2009 Cardiac MR Left Ventricle Segmentation Challenge. Correct LV localization was confirmed in 97.3% of the datasets. The mean absolute error between the gold standard and localization centroids was 2.8 to 4.7 mm, or 12 to 22% of the average endocardial radius. Graphical abstract Fully automated localization of the left ventricular blood pool in short axis cardiac cine MR images.

  6. Alterations of the blood pool in the femoral head before and after renal transplantation

    International Nuclear Information System (INIS)

    Hamaguchi, Hiroyuki; Fujioka, Mikihiro; Inoue, Shigehiro; Shibatani, Masahiko; Kubo, Toshikazu; Kubota, Takao; Ushijima, Yo; Nishimura, Tsunehiko

    2003-01-01

    The pathogenesis of idiopathic osteonecrosis of the femoral head (ION) is thought to be an ischemic event. The purpose of this study is to investigate alterations of the blood pool in the femoral head before and after renal transplantation. After renal transplantation, all patients received the same immunosuppressive therapy: corticosteroids, cyclosporin-A, and azathioprine. We performed 3-phase bone scintigraphy on 16 renal allograft recipients within 1 week before renal transplantation, and between week 4 and 9 after renal transplantation. Regions of interest (ROI) were assigned bilaterally in the femoral head, diaphysis, and soft tissue. The head-to-diaphysis ratios (HD ratios) were then calculated. Idiopathic osteonecrosis of the femoral head occurred in 2 femoral heads of 1 patient. The HD ratio before renal transplantation (mean HD±SD, 1.52±0.30) and the HD ratio after renal transplantation (1.28±0.30) were significantly different (P=0.000024). The HD ratios before and after renal transplantation were significantly different, indicating that the administration of steroids diminished the blood pool in the femoral head. A low HD ratio before renal transplantation revealed a poor blood pool in the femoral head, which may be a risk factor for ION. (author)

  7. Gene expression changes in blood RNA after swimming in a chlorinated pool.

    Science.gov (United States)

    Salas, Lucas A; Font-Ribera, Laia; Bustamante, Mariona; Sumoy, Lauro; Grimalt, Joan O; Bonnin, Sarah; Aguilar, Maria; Mattlin, Heidi; Hummel, Manuela; Ferrer, Anna; Kogevinas, Manolis; Villanueva, Cristina M

    2017-08-01

    Exposure to disinfection by-products (DBP) such as trihalomethanes (THM) in swimming pools has been linked to adverse health effects in humans, but their biological mechanisms are unclear. We evaluated short-term changes in blood gene expression of adult recreational swimmers after swimming in a chlorinated pool. Volunteers swam 40min in an indoor chlorinated pool. Blood samples were drawn and four THM (chloroform, bromodichloromethane, dibromochloromethane and bromoform) were measured in exhaled breath before and after swimming. Intensity of physical activity was measured as metabolic equivalents (METs). Gene expression in whole blood mRNA was evaluated using IlluminaHumanHT-12v3 Expression-BeadChip. Linear mixed models were used to evaluate the relationship between gene expression changes and THM exposure. Thirty-seven before-after pairs were analyzed. The median increase from baseline to after swimming were: 0.7 to 2.3 for MET, and 1.4 to 7.1μg/m 3 for exhaled total THM (sum of the four THM). Exhaled THM increased on average 0.94μg/m 3 per 1 MET. While 1643 probes were differentially expressed post-exposure. Of them, 189 were also associated with exhaled levels of individual/total THM or MET after False Discovery Rate. The observed associations with the exhaled THM were low to moderate (Log-fold change range: -0.17 to 0.15). In conclusion, we identified short-term gene expression changes associated with swimming in a pool that were minor in magnitude and their biological meaning was unspecific. The high collinearity between exhaled THM levels and intensity of physical activity precluded mutually adjusted models with both covariates. These exploratory results should be validated in future studies. Copyright © 2017. Published by Elsevier B.V.

  8. 99mTc-MDP combined blood pool and bone phase radionuclide imaging in papain-injected carpal joints

    International Nuclear Information System (INIS)

    Metcalf, M.R.; Twardock, A.R.; Sanecki, R.K.

    1985-01-01

    Scintigraphic changes, i.e., increased activity, were induced by 1% papain, dissolved in phosphate-buffered physiologic saline (pH 7.4), injected into one antebrachiocarpal joint in each of eight dogs. Scintigraphic evaluation was by the use of combined blood pool and bone phase scintigraphy of affected and normal carpi over a 28-day period. The qualitative and quantitative scintigraphic appearance in injected carpal joints were very similar in both blood pool and bone phases. The clinical use of combined blood pool and bone phase scintigraphy to diagnose early inflammatory joint changes appears limited

  9. Application of blood-pool agents in visualization of peripheral vessels

    International Nuclear Information System (INIS)

    Giovagnoni, A.; Catalano, C.

    2007-01-01

    Effective arterial imaging is essential in patients with peripheral arterial disease (PAD) in whom a revascularization procedure is planned. Digital subtraction angiography (DSA) has traditionally been regarded as the gold standard for imaging in peripheral arterial disease, but this technique is subject to certain limitations, such as the risks of adverse reactions associated with arterial catheterization and iodinated contrast agents. Contrast-enhanced magnetic resonance angiography is now recommended as an effective and useful imaging technique in peripheral arterial disease, since it offers high enhanced contrast between blood and stationary tissue and fast acquisition times. However, extracellular gadolinium contrast agents rapidly diffuse into the interstitial spaces, and thus are suitable only for first-pass imaging. This limitation can be overcome by the use of blood-pool (intravascular) contrast agents, such as gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany), which are retained within the blood vessels and hence facilitate both first-pass and steady-state imaging with high spatial resolution. Blood-pool agents, therefore, offer improved imaging, particularly of distal vessels, compared with extracellular contrast agents. Examples of first-pass and steady-state imaging with gadofosveset are presented. (orig.)

  10. Self-Assembled Nanomicelles as MRI Blood-Pool Contrast Agent.

    Science.gov (United States)

    Babič, Andrej; Vorobiev, Vassily; Xayaphoummine, Céline; Lapicorey, Gaëlle; Chauvin, Anne-Sophie; Helm, Lothar; Allémann, Eric

    2018-01-26

    Gadolinium-loaded nanomicelles show promise as future magnetic resonance imaging (MRI) contrast agents (CAs). Their increased size and high gadolinium (Gd) loading gives them an edge in proton relaxivity over smaller molecular Gd-complexes. Their size and stealth properties are fundamental for their long blood residence time, opening the possibility for use as blood-pool contrast agents. Using l-tyrosine as a three-functional scaffold we synthesized a nanostructure building block 8. The double C18 aliphatic chain on one side, Gd-1,4,7,10-tetraazacyclododecane-1-4-7-triacetic acid (Gd-DO3A) with access to bulk water in the center and 2 kDa PEG on the hydrophilic side gave the amphiphilic properties required for the core-shell nanomicellar architecture. The self-assembly into Gd-loaded monodispersed 10-20 nm nanomicelles occurred spontaneously in water. These nanomicelles (Tyr-MRI) display very high relaxivity at 29 mm -1  s -1 at low field strength and low cytotoxicity. Good contrast enhancement of the blood vessels and the heart together with prolonged circulation time in vivo, makes Tyr-MRI an excellent candidate for a new supramolecular blood-pool MRI CA. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Gallium-68-DOTA-albumin as a PET blood-pool marker: experimental evaluation in vivo

    International Nuclear Information System (INIS)

    Hoffend, Johannes; Mier, Walter; Schuhmacher, Jochen; Schmidt, Kerstin; Dimitrakopoulou-Strauss, Antonia; Strauss, Ludwig G.; Eisenhut, Michael; Kinscherf, Ralf; Haberkorn, Uwe

    2005-01-01

    Investigations into tumor angiogenesis and antiangiogenic treatment have renewed interest in tumor perfusion. To image tumor blood-pool by PET, suitable tracers are not generally available. In this experimental study, we characterized a 68 Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugate of rat serum albumin ( 68 Ga-DOTA-RSA) in vivo using a generator-produced isotope. Biodistribution was determined in ACI rats after intravenous administration of 3-6 MBq of 68 Ga-DOTA-RSA. Three ACI rats were imaged over 1 h by dynamic PET after intravenous administration of 15-25 MBq of 68 Ga-DOTA-RSA while the blood-pool activity was recorded simultaneously in a closed extracorporeal loop (ECL) between the carotid artery and the jugular vein. Time-activity curves (TACs) were obtained from volume of interest (VOI) analysis and from the ECL data. Stability and metabolites in plasma and urine were analyzed by size exclusion HPLC (SE-HPLC) 1 h after intravenous injection of 67 Ga-DOTA-RSA. Blood radioactivity decreased by 10% and 18% from 10 to 60 min p.i. by biodistribution and PET or ECL, respectively. Tissue sampling between 10 and 60 min p.i. showed slight increases in the uptake of spleen, myocardium, kidney and skeletal muscle while hepatic accretion remained unchanged. Total urinary excretion after 60 min amounted to 9% of the injected dose. HPLC demonstrated a single urinary metabolite corresponding in size to gallium-labeled DOTA. 68 Ga-DOTA-RSA is a blood-pool tracer whose physical and biological half-life is well suited for PET. Our findings support clinical imaging using 68 Ga-DOTA-labeled human serum albumin (HSA). The generator-produced label makes 68 Ga-DOTA-labeled albumin continuously available even to centers lacking an in-house cyclotron

  12. Clinical comparison of cardiac blood pool visualization with technetium-99m red blood cells labeled in vivo and with technetium-99m human serum albumin

    International Nuclear Information System (INIS)

    Thrall, J.H.; Freitas, J.E.; Swanson, D.; Rogers, W.L.; Clare, J.M.; Brown, M.L.; Pitt, B.

    1978-01-01

    Technetium-99m red blood cells (Tc-RBC) labeled by an in vivo technique were compared with two preparations of Tc-99m human serum albumin (HSA) for cardiac blood-pool imaging. Relative distribution of the tracers was analyzed on end-diastolic frames of gated blood-pool studies and on whole-body (head to mid-thigh) anterior pinhole images. The Tc-RBC demonstrated greater relative percentage localization in the cardiac blood pool, higher target-to-background ratios in the left ventricle, and less liver concentration. For cardiac blood-pool imaging, Tc-RBC labeled by the in vivo approach appears to be superior to the two Tc-HSA preparations studied

  13. Development of Tc-99m-DTPA-HSA as a new blood pool scanning agent

    Energy Technology Data Exchange (ETDEWEB)

    Shirakami, Y; Matsumoto, Y; Yamauchi, Y; Kurami, M; Ueda, N; Hazue, M

    1987-04-01

    A new HSA preparation, Tc-99m-DTPA-HSA, was developed as a blood pool scanning agent. It shows higher labeling yield (more than 95 %) and higher blood retention (74.7 % I.D. at 1 hour post-injection) than Tc-99m-HSA prepared by directly labeling of HSA with Tc-99m. The introduction of DTPA, a strong bifunctional chelating agent, to HSA provides sites for the stable binding of Tc-99m. The preparation composed of 20 mCi of Tc-99m at calibration time and 10 mg of DTPA-HSA in a vial. After labeling, it had been stable for 24 hours at room temperature. In rats, most of Tc-99m-DTPA-HSA injected was metabolized and excreted in urine and feces. The cumulative radioactivity in urine and feces were 56.0 % and 13.7 % of injected dose, respectively, at 48 hours after injection. Metabolites observed in urine were Tc-99m-urea, Tc-99m-DTPA, reduced Tc-99m and so on. Tc-99m-DTPA-HSA proved, thus, a desirable feature for the blood pool scanning agent.

  14. Detection of soft tissue pathology on the blood pool phase of bone scans

    International Nuclear Information System (INIS)

    Raimondo, A.J.; Turner, H.A.; Kitchener, M.I.

    1999-01-01

    Full text: It is important to optimize information obtained from isotope bone scanning in musculoskeletal imaging. Although important at all times, it is especially imperative in the current climate of health services rationalization, capping of imaging expenditure and the promotion of newer modalities that are increasingly versatile and sensitive for imaging the musculoskeletal system. Careful attention must be paid to the blood flow and blood pool images, to visualize soft tissue as well as bony pathology. A series of cases and images will be presented that demonstrated blood pool pathology that was not appreciated on delayed imaging, or where reliance only on the delayed images would have led to an incorrect diagnosis. These include the detection of tendonitis, tenosynovitis, bursitis, muscle tears and soft tissue neoplasms, including neuromas. In cases where the bone scan cannot provide a definitive diagnosis, it will at least direct the referring clinician to the most appropriate confirmatory diagnostic imaging modality, thus reinforcing the value that isotope imaging provides in musculoskeletal medicine

  15. Gated cardiac blood pool studies in atrial fibrillation: Role of cycle length windowing

    Energy Technology Data Exchange (ETDEWEB)

    Wallis, J W; Juni, J E; Wu, L [Michigan Univ., Ann Arbor (USA). Div. of Nuclear Medicine

    1991-01-01

    Cycle length windowing is gaining increasing acceptance in gated blood pool imaging of patients with atrial fibrillation (AF). The goals of this study were: to assess differences of ejection fraction (EF) in AF with and without windowing and to determine how EF varied with cycle length in patients with AF. Twenty patients with AF were prospectively studied by gated blood pool imaging, with simultaneous collection in each patient of 5-7 studies with cycle length windows spanning the cycle length histogram. Each window accepted beats of only a narrow range of cycle lengths. EF was determined for each of the narrow cycle length windows as well as for the entire gated blood pool study without cycle length windowing. For every patient an average of the windowed EFs was compared with the non-windowed EF. EF values were similar (mean windowed: 46.6; non-windowed: 45.5; P=0.16), and there was a good correlation between the two techniques (r=0.97). The data were then examined for a relationship of EF with cycle length. The difference from average windowed EF ({Delta}EF) was calculated for each window and plotted vs. the cycle length of the center of each window. No predictable linear or nonlinear relationship of {Delta}EF with window position was observed. Lack of predictable variation of EF with cycle length is likely due to lack of a predictable amount of ventricular filling for a given cycle length, as the amount of diastolic filling in AF depends on the random cycle length of the preceding beat. In summary, windowing in AF does not provide a clinically significant difference in EF determination. If cycle length windowing is used, the exact location of the window is not critical. (orig.).

  16. Dynamic circular buffering: a technique for equilibrium gated blood pool imaging.

    Science.gov (United States)

    Vaquero, J J; Rahms, H; Green, M V; Del Pozo, F

    1996-03-01

    We have devised a software technique called "dynamic circular buffering" (DCB) with which we create a gated blood pool image sequence of the heart in real time using the best features of LIST and FRAME mode methods of acquisition/processing. The routine is based on the concept of independent "agents" acting on the timing and position data continuously written into the DCB. This approach allows efficient asynchronous operation on PC-type machines and enhanced capability on systems capable of true multiprocessing and multithreading.

  17. Evaluating the pacemaker effect with the pump parameter of gated blood-pool imaging

    International Nuclear Information System (INIS)

    Cheng Muhua

    1995-01-01

    13 normal controls and 27 patients with ventricular pacemaker had undergone planar gated blood-pool imaging in different conditions. Result shows: (1) Pump parameters can successfully reflect therapeutic effect of pacemaker among them EMP is the most valuable parameter for evaluating the cardiac pumping effect. (2) After implantation of the ventricular pacemaker, the LVEF did not increase, but the CO and EMP was significantly increased. (3) Compared with right ventricular demand pacemaker, the rate-responsive ventricular pacemaker give better hemodynamic benefit at exercise condition. (4) Through restrained cardiac pacemaker the functional change was analyzed on or off pace, and monitoring the cardiac function itself after the pacemaker was implanted

  18. Technical requirements, biophysical considerations and protocol optimization with magnetic resonance angiography using blood-pool agents

    International Nuclear Information System (INIS)

    Rohrer, M.; Geerts-Ossevoort, L.; Laub, G.

    2007-01-01

    In order to maximize the potential benefits of contrast-enhanced magnetic resonance angiography, careful attention must be paid to the choice of hardware, data acquisition and processing, and to the choice of contrast agent. Typically, contrast-enhanced magnetic resonance angiography uses parallel-imaging techniques, which shorten the acquisition time, enhance spatial resolution and reduce artefacts. The timing of data acquisition is crucial for maximal enhancement of the arteries: for optimal arterial depiction, the centre of k-space should be acquired at the time of peak concentration of contrast agent in the arterial bed being investigated, and a number of k-space acquisition techniques are available to achieve this. SENSE or GRAPPA techniques can be used to facilitate parallel-imaging reconstruction of either the image data or k-space data, respectively. Gadolinium contrast agents shorten the proton relaxation times (most importantly T1) of blood, thereby increasing the signal-to-noise ratio and enhancing differentiation between blood vessels and other tissues. The blood-pool (intravascular) contrast agent gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany) is reversibly protein-bound in human plasma. This results in a marked increase in relaxivity, and hence a strong T1 shortening effect compared with other gadolinium-based contrast agents. Furthermore, the blood retention time of gadofosveset trisodium is substantially prolonged compared with conventional contrast agents. As a result, gadofosveset trisodium permits both first-pass and steady-state imaging. (orig.)

  19. Synthesis of fluorine-18 radio-labeled serum albumins for PET blood pool imaging

    International Nuclear Information System (INIS)

    Basuli, Falguni; Li, Changhui; Xu, Biying; Williams, Mark; Wong, Karen; Coble, Vincent L.; Vasalatiy, Olga; Seidel, Jurgen; Green, Michael V.; Griffiths, Gary L.; Choyke, Peter L.; Jagoda, Elaine M.

    2015-01-01

    We sought to develop a practical, reproducible and clinically translatable method of radiolabeling serum albumins with fluorine-18 for use as a PET blood pool imaging agent in animals and man. Fluorine-18 radiolabeled fluoronicotinic acid-2,3,5,6-tetrafluorophenyl ester, [ 18 F]F-Py-TFP was prepared first by the reaction of its quaternary ammonium triflate precursor with [ 18 F]tetrabutylammonium fluoride ([ 18 F]TBAF) according to a previously published method for peptides, with minor modifications. The incubation of [ 18 F]F-Py-TFP with rat serum albumin (RSA) in phosphate buffer (pH 9) for 15 min at 37–40 °C produced fluorine-18-radiolabeled RSA and the product was purified using a mini-PD MiniTrap G-25 column. The overall radiochemical yield of the reaction was 18–35% (n = 30, uncorrected) in a 90-min synthesis. This procedure, repeated with human serum albumin (HSA), yielded similar results. Fluorine-18-radiolabeled RSA demonstrated prolonged blood retention (biological half-life of 4.8 hours) in healthy awake rats. The distribution of major organ radioactivity remained relatively unchanged during the 4 hour observation periods either by direct tissue counting or by dynamic PET whole-body imaging except for a gradual accumulation of labeled metabolic products in the bladder. This manual method for synthesizing radiolabeled serum albumins uses fluorine-18, a widely available PET radionuclide, and natural protein available in both pure and recombinant forms which could be scaled up for widespread clinical applications. These preclinical biodistribution and PET imaging results indicate that [ 18 F]RSA is an effective blood pool imaging agent in rats and might, as [ 18 F]HSA, prove similarly useful as a clinical imaging agent

  20. Synthesis of fluorine-18 radio-labeled serum albumins for PET blood pool imaging.

    Science.gov (United States)

    Basuli, Falguni; Li, Changhui; Xu, Biying; Williams, Mark; Wong, Karen; Coble, Vincent L; Vasalatiy, Olga; Seidel, Jurgen; Green, Michael V; Griffiths, Gary L; Choyke, Peter L; Jagoda, Elaine M

    2015-03-01

    We sought to develop a practical, reproducible and clinically translatable method of radiolabeling serum albumins with fluorine-18 for use as a PET blood pool imaging agent in animals and man. Fluorine-18 radiolabeled fluoronicotinic acid-2,3,5,6-tetrafluorophenyl ester, [(18)F]F-Py-TFP was prepared first by the reaction of its quaternary ammonium triflate precursor with [(18)F]tetrabutylammonium fluoride ([(18)F]TBAF) according to a previously published method for peptides, with minor modifications. The incubation of [(18)F]F-Py-TFP with rat serum albumin (RSA) in phosphate buffer (pH9) for 15 min at 37-40 °C produced fluorine-18-radiolabeled RSA and the product was purified using a mini-PD MiniTrap G-25 column. The overall radiochemical yield of the reaction was 18-35% (n=30, uncorrected) in a 90-min synthesis. This procedure, repeated with human serum albumin (HSA), yielded similar results. Fluorine-18-radiolabeled RSA demonstrated prolonged blood retention (biological half-life of 4.8 hours) in healthy awake rats. The distribution of major organ radioactivity remained relatively unchanged during the 4 hour observation periods either by direct tissue counting or by dynamic PET whole-body imaging except for a gradual accumulation of labeled metabolic products in the bladder. This manual method for synthesizing radiolabeled serum albumins uses fluorine-18, a widely available PET radionuclide, and natural protein available in both pure and recombinant forms which could be scaled up for widespread clinical applications. These preclinical biodistribution and PET imaging results indicate that [(18)F]RSA is an effective blood pool imaging agent in rats and might, as [(18)F]HSA, prove similarly useful as a clinical imaging agent. Published by Elsevier Inc.

  1. Comparison of transaxial source images and 3-plane, thin-slab maximal intensity projection images for the diagnosis of coronary artery stenosis with using ECG-gated cardiac CT

    International Nuclear Information System (INIS)

    Choi, Jin Woo; Seo, Joon Beom; Do, Kyung Hyun

    2006-01-01

    We wanted to compare the transaxial source images with the optimized three plane, thin-slab maximum intensity projection (MIP) images from electrocardiographic (ECG)-gated cardiac CT for their ability to detect hemodynamically significant stenosis (HSS), and we did this by means of performing a receiver operating characteristic (ROC) analysis. Twenty-eight patients with a heart rate less than 66 beats per minute and who were undergoing both retrospective ECG-gated cardiac CT and conventional coronary angiography were included in this study. The contrast-enhanced CT scans were obtained with a collimation of 16 x 0.75-mm and a rotation time of 420 msec. The tranaxial images were reconstructed at the mid-diastolic phase with a 1-mm slice thickness and a 0.5-mm increment. Using the transaxial images, the slab MIP images were created with a 4-mm thickness and a 2-mm increment, and they covered the entire heart in the horizontal long axis (4 chamber view), in the vertical long axis (2 chamber view) and in the short axis. The transaxial images and MIP images were independently evaluated for their ability to detect HSS. Conventional coronary angiograms of the same study group served as the standard of reference. Four radiologists were requested to rank each image with using a five-point scale (1 = definitely negative, 2 = probably negative, 3 = indeterminate, 4 = probably positive, and 5 definitely positive) for the presence of HSS; the data were then interpreted using ROC analysis. There was no statistical difference in the area under the ROC curve between transaxial images and MIP images for the detection of HSS (0.8375 and 0.8708, respectively; ρ > 0.05). The mean reading time for the transaxial source images and the MIP images was 116 and 126.5 minutes, respectively. The diagnostic performance of the MIP images for detecting HSS of the coronary arteries is acceptable and this technique's ability to detect HSS is comparable to that of the transaxial source images

  2. Investigations of new cardiac functional imaging using Fourier analysis of gated blood-pool study

    International Nuclear Information System (INIS)

    Maeda, H.; Takeda, K.; Nakagawa, T.; Yamaguchi, N.; Taguchi, M.; Konishi, T.; Hamada, M.

    1982-01-01

    A new cardiac functional imaging, using temporal Fourier analysis of 28-frame gated cardiac blood-pool studies, was developed. A time-activity curve of each pixel was approximated by its Fourier series. Approximation by the sum for terms to the 3rd frequency of its Fourier series was considered to be most reasonable because of having the least aberration due to statistical fluctuation and close agreement between the global left ventricular curve and the regional fitted curves in normal subjects. To evaluate the ventricular systolic and diastolic performances, 9 parameters were analyzed from thus fitted curves on a pixel-by-pixel basis and displayed on a colour CRT in 64x64 matrix form. In patients with hypertrophic obstructive cardiomyopathy and other cardiac lesions, detailed information on the regional ventricular systolic and diastolic performances was clearly visualized by this method, which was difficult to obtain from the usual functional images of phase and amplitude at the fundamental frequency alone

  3. Patterns of ventricular dysfunction in patients receiving cardiotoxic chemotherapy as assessed with gated blood pool imaging

    International Nuclear Information System (INIS)

    Spies, S.M.; Parikh, S.R.; Spies, W.G.; Zimmer, A.M.; Silverstein, E.A.

    1989-01-01

    Clinical concern over significant cardiotoxicity of commonly employed chemotherapeutic regimens is a common indication for gated blood pool imaging. The authors have undertaken a review of 102 patients referred for such evaluation during a 14-month period. Ventricular ejection fractions, cine displays, and phase analysis were performed on each patient study. Approximately one-third of the cases showed significant abnormalities in wall motion or global ejection fraction. Many abnormal cases had isolated left ventricular findings, while fewer had isolated right ventricular findings. Left ventricular wall motion abnormalities were often focal. The patterns of ventricular dysfunction in patients receiving cardiotoxic chemotherapy are diverse, and awareness of the various possibilities is important for accurate clinical assessment of these patients

  4. Right-sided phase abnormalities on gated blood pool ventriculography: Demonstration of six different patterns

    International Nuclear Information System (INIS)

    Bahar, R.H.; Abdel-Dayem, H.M.; Ziada, G.; Al-Suhali, A.; Constantinides, C.; Nair, K.M.

    1986-01-01

    Phase pattern abnormalities on multiple gated blood pool ventriculography are better reported for the left ventricle (LV) than for the right side of the heart. In a study of 92 patients who also underwent contrast ventriculography, the authors identified six different patterns of right-sided phase abnormalities and their causes: right bundle-branch block, causing delayed phase in the entire right ventricle (RV); ischemic right coronary artery disease, causing delayed phase in the inferior RV wall; pericardial effusion, causing an L-shaped area of delayed phase to the right of the septum and below the LV; pulmonary hypertension, causing delayed phase in the pulmonary infundibulum; tricuspid regurgitation, causing a crescentic area of delayed phase around and below the right RV and extending below the LV as well, and atrial septal defect causing an abnormally large auricular phase

  5. Clinical validation of fully automated computation of ejection fraction from gated equilibrium blood-pool scintigrams

    International Nuclear Information System (INIS)

    Reiber, J.H.C.; Lie, S.P.; Simoons, M.L.; Hoek, C.; Gerbrands, J.J.; Wijns, W.; Bakker, W.H.; Kooij, P.P.M.

    1983-01-01

    A fully automated procedure for the computation of left-ventricular ejection fraction (EF) from cardiac-gated Tc-99m blood-pool (GBP) scintigrams with fixed, dual, and variable ROI methods is described. By comparison with EF data from contrast ventriculography in 68 patients, the dual-ROI method (separate end-diastolic and end-systolic contours) was found to be the method of choice; processing time was 2 min. Success score of dual-ROI procedure was 92% as assessed from 100 GBP studies. Overall reproducibility of data acquisition and analysis was determined in 12 patients. Mean value and standard deviation of differences between repeat studies (average time interval 27 min) were 0.8% and 4.3% EF units, respectively, (r=0.98). The authors conclude that left-ventricular EF can be computed automatically from GBP scintigrams with minimal operator-interaction and good reproducibility; EFs are similar to those from contrast ventriculography

  6. Detecting early cardiac dysfunction with radionuclide cardiac blood-pool imaging

    International Nuclear Information System (INIS)

    Wu Kegui; Chen Daguang; Lin Haoxue

    1992-01-01

    Cardiac function was measured by radionuclide cardiac blood-pool imaging in 15 normal persons, 19 cases of hypertension, 32 cases of coronary heart disease, 35 cases of coronary heart disease combined with hypertension and 44 cases of myocardial infarction. Significant differences have been found in indices of cardiac function between normal subjects and patients with coronary heart disease and coronary heart disease combined with hypertension, even though the patients were without any clinical sin of cardiac failure. Lowered regional EF and decreased ventricular was motion were found in 38.8% of patients, while 65.7%of patients revealed marked abnormality in MFR. The results indicate that latent cardiac dysfunction is common in patients with coronary heart disease. The earliest change is diastolic function abnormalities

  7. The values of myocardial tomography imaging and gated cardiac blood pool imaging in detecting left ventricular aneurysm

    International Nuclear Information System (INIS)

    Zhu Mei; Pan Zhongyun; Li Jinhui

    1992-01-01

    The sensitivity and specificity of myocardial tomography imaging and gated cardiac blood-pool imaging in detecting LVA were studied in 36 normal subjects and 68 patients with myocardial infarction. The sensitivities of exercise and rest myocardial imaging in detecting LVA were 85% and 77.3% respectively. The specificity of both is 95.5%. The sensitivity of cinema display, phase analysis and left ventricular phase shift in evaluating LVA were 86.7%, 86.7%, 100% respectively. Their specificity were all 100%. It is concluded that blood pool imaging is of choice for the diagnosis of LVA, and that myocardial imaging could also demonstrate LVA during diagnosing myocardial infarction

  8. Incremental value of regional wall motion analysis immediately after exercise for the detection of single-vessel coronary artery disease. Study by separate acquisition, dual-isotope ECG-gated single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Yoda, Shunichi; Sato, Yuichi; Matsumoto, Naoya; Tani, Shigemasa; Takayama, Tadateru; Uchiyama, Takahisa; Saito, Satoshi

    2005-01-01

    Although the detection of wall motion abnormalities gives incremental value to myocardial perfusion single-photon emission computed tomography (SPECT) in the diagnosis of extensive coronary artery disease (CAD) and high-grade single-vessel CAD, whether or not it is useful in the diagnosis of mild, single-vessel CAD has not been studied previously. Separate acquisition, dual isotope electrocardiogram (ECG)-gated SPECT was performed in 97 patients with a low likelihood of CAD (Group 1) and 46 patients with single-vessel CAD (Group 2). Mild CAD was defined by stenosis of 50-75% (Group 2a, n=22) and moderate to severe CAD was defined by stenosis ≥76% (Group 2b, n=24). Myocardial perfusion and wall motion were graded by a 5 point-scale, 20-segment model. The sensitivity of myocardial perfusion alone was 50% for Group 2a, 83% for Group 2b and 67% for Group 2 as a whole. The overall specificity was 90%. When the wall motion analysis was combined, the sensitivity was increased to 82% in Group 2a and 92% in Group 2b. The ability to detect a wall motion abnormality immediately after exercise gives incremental diagnostic value to myocardial perfusion SPECT in the identification of mild, single-vessel CAD. (author)

  9. Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

    International Nuclear Information System (INIS)

    Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil

    1985-01-01

    The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

  10. Whole-body magnetic resonance angiography with blood-pool agents

    International Nuclear Information System (INIS)

    Kramer, H.; Morana, G.

    2007-01-01

    Although often asymptomatic, peripheral arterial disease (PAD) is associated with significant morbidity in a large proportion of patients. Atherosclerosis is the underlying pathology in many instances, involving the whole arterial tree. Whole-body magnetic resonance angiography (MRA) permits rapid, non-invasive and accurate evaluation of the entire vascular system and can be used for both diagnostic purposes and monitoring of vascular involvement in diseases such as diabetes, Marfan's syndrome and Takayasu arteritis. MRA has been used successfully in the identification of high-grade stenosis in PAD, abnormalities of the ileocaval veins and carotid plaque imaging. Carotid disease is significantly correlated with severe coronary artery disease and renal artery atherosclerosis. Symptomatic lesions in one vascular bed are often related to additional asymptomatic atherosclerotic lesions in other vascular regions. MRA may be advantageous over computed tomographic angiography because it can be performed with contrast media virtually devoid of serious toxicity and without utilization of ionizing radiation. Display of the entire arterial vasculature can be achieved in < 90 s, with excellent sensitivity and specificity. Recent technological advances, such as parallel imaging and the implementation of dedicated matrix coils, have further increased image quality, and in combination with the blood-pool contrast agents, such as gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany), extended imaging time, higher spatial resolution and larger anatomical coverage can be achieved. (orig.)

  11. Whole-body magnetic resonance angiography with blood-pool agents

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, H. [Inst. for Clinical Radiology, Univ. Hospital Munich, Munich (Germany); Morana, G. [Radiological Dept., Hospital Ca' Foncello, Treviso (Italy)

    2007-03-15

    Although often asymptomatic, peripheral arterial disease (PAD) is associated with significant morbidity in a large proportion of patients. Atherosclerosis is the underlying pathology in many instances, involving the whole arterial tree. Whole-body magnetic resonance angiography (MRA) permits rapid, non-invasive and accurate evaluation of the entire vascular system and can be used for both diagnostic purposes and monitoring of vascular involvement in diseases such as diabetes, Marfan's syndrome and Takayasu arteritis. MRA has been used successfully in the identification of high-grade stenosis in PAD, abnormalities of the ileocaval veins and carotid plaque imaging. Carotid disease is significantly correlated with severe coronary artery disease and renal artery atherosclerosis. Symptomatic lesions in one vascular bed are often related to additional asymptomatic atherosclerotic lesions in other vascular regions. MRA may be advantageous over computed tomographic angiography because it can be performed with contrast media virtually devoid of serious toxicity and without utilization of ionizing radiation. Display of the entire arterial vasculature can be achieved in < 90 s, with excellent sensitivity and specificity. Recent technological advances, such as parallel imaging and the implementation of dedicated matrix coils, have further increased image quality, and in combination with the blood-pool contrast agents, such as gadofosveset trisodium (Vasovist, Bayer Schering Pharma AG, Berlin, Germany), extended imaging time, higher spatial resolution and larger anatomical coverage can be achieved. (orig.)

  12. Quantification of the temporal component of left ventricular asynergy by gated cardiac blood pool scans

    International Nuclear Information System (INIS)

    Solot, G.; Chevigne, M.; Rigo, P.

    1985-01-01

    Fourier analysis (F) has demonstrated that left ventricular (LV) dysfunction can be analyzed in two separate component: an amplitude (AM) and a temporal (T) component. Although the former dominates in hypokinesis and akinesis, and the latter in dyskinesis, they are almost always associated and combine to determine the clinical form of asynergy (AS). The mechanical consequences of the T component cannot be assessed continuously by F which requires setting of a threshold. In this study, the authors have analyzed the potential of a new index; the stroke volume efficiency (SV Eff) to evaluate the importance of T AS in patients (pts) with coronary artery disease studied by gated blood pool scans. The authors have studied 14 controls, 8 pts with coronary artery disease without infarction, 56 pts with myocardial infarction (MI) and 21 pts with LV aneurysm. The SV Eff was calculated as follows after normalization and smoothing of the series: maximum and minimum images were created first and a LV region of interest was traced using the F AM image. The SV Eff ratio was calculated within the LV region of interest as ''diastolic counts - systolic counts/maximum counts - minimum counts''. The SV Eff in controls was 94% +- 2. The authors conclude that SV Eff provides a quantitative measurement of T component of LV dysfunction and an estimate of the dyskinetic component in pts with LV aneurysm. It should prove useful to study these patients serially

  13. Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1985-03-15

    The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

  14. Comparison of left ventricular ejection fraction by 201Tl gated SPECT and gated blood pool scan

    International Nuclear Information System (INIS)

    Lau, W.F.E.; Kelly, M.J.; O'Donnell, M.; Kalff, V.; Van Every, B.

    2000-01-01

    Full text: The aim of this study was to evaluate left ventricular ejection fraction (LVEF) determination by the Germano 201 Tl gated-SPECT myocardial perfusion (TLGSMP) method using gated blood pool scintigraphy (GBPS) as a reference. 21 patients underwent both TLGSMP and GBPS within eight days of each other from June 1997 to Jan 2000. Acquisition of TLGSMP was performed on a GE Optima NX dual head camera using Tl-201 dose of 1.5MBq/Kg and imaging time of 45 cardiac cycles/step with 16 steps/90 Deg of rotation per detector. All LVEF results were determined using a GE Genie workstation. GBPS results were compared with TLGSMP results for LVEF obtained from the reinjection images using automated Germano processing, and from the stress images using automatic and manual processing. Duplicate automatic analysis by a second observer produced identical mean TLGSMP LVEF results (r = 0.99). Stress TLGSMP LVEF by the automatic and manual processing correlate well (r = 0.99) but the manual LVEF is significantly lower. In conclusion LVEF determination using TLGSMP is highly reproducible and is also accurate when applied to reinjection data. Both manual processing and the use of stress data lead to underestimation of LVEF. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  15. Dynamic arrythmia filtration for gated blood pool imaging: Validation against list - Mode technique

    International Nuclear Information System (INIS)

    Juni, J.E.; Wallis, J.; Rocchini, A.; Wu-Connolly, L.

    1985-01-01

    Normal resting heart rate variation distort the diastolic portions of time-activity curves (TACs) generated from gated blood pool (GBP) images. This alters calculated measures of diastolic function e.g. peak filling rate (PFR). The authors compared diastolic filling parameters obtained by two methods of arrythmia removal, list-mode (LM) acquisition and a new approach, dynamic arrythima filtration (DAF). LM acquisition techniques reject beats of unusual cycle length, thus reducing the TAC distortions caused by heart rate variation but is time consuming and requires large amounts of disk storage. In DAF systems data is evaluated for cycle length in real-time and accepted or rejected immediately according to preset, operator determined cycle-length criteria, thus eliminating the need for post-processing of data and for large mass data storage. The authors prospectively determined EF, time to end-systole (TES), PFR, ad TPFR on 25 GBP patients. Camera and ECG data were sent simultaneously to 2 computers. One acquired data via LM and the other by DAF. Fluctuations in heart rate during GBP acquisition may cause errors in calculation of filling parameters. Both LM and DAF remove cycles of unusual length. DAF is less time consuming and technically demanding than LM and provides results which correlate closely with those obtained by LM

  16. Pulmonary capillary wedge pressure, as inferred from lung areas in gated blood-pool scintigrams: concise communication

    International Nuclear Information System (INIS)

    Urbina, A.; Okada, R.D.; Palacios, I.; Osbakken, M.; Strauss, H.W.

    1981-01-01

    To determine whether the apex-to-base distribution of pulmonary blood volume, as obtained from gated cardiac blood-pool scans, could be used as a noninvasive method to estimate mean pulmonary capillary wedge pressure (PCWP), gated blood-pool scans were analyzed in 77 patients who also had PCWP measurements at cardiac catheterization. Ten of these patients had gated cardiac blood-pool scans and PCWP measurements both at rest and during exercise. The apex-to-base distribution of pulmonary blood volume was determined from the end-systolic frame of the left anterior oblique view by placing equal-sized regions of interest over the apex and base of the right lung. The ratio of apex counts over base counts (A/B ratio) was considered abnormal if greater than unity. The mean A/B ratio was 1.15 +/- 0.27 (1 s.d.) for the 32 studies associated with an abnormal mean PCWP (greater than 12 mm Hg). The mean A/B ratio was 0.85 +/- 0.23 for the 55 studies associated with a normal mean PCWP (p less than 0.01 comparing normal group with abnormal). The sensitivity of the A/B ratio for a mean PCWP greater than 12 mm Hg was 81%R (26/32). The specificity of the A/B ratio for a mean PCWP greater than or equal to 12 mm Hg was 89% (49/55). Thus, noninvasive determination of the pulmonary apex-to-base ratio from gated cardiac blood-pool scans appears to differentiate subjects with normal and abnormal mean pulmonary capillary wedge pressures

  17. Magnetic resonance angiography (MRA) of the calf station at 3.0 T: intraindividual comparison of non-enhanced ECG-gated flow-dependent MRA, continuous table movement MRA and time-resolved MRA

    International Nuclear Information System (INIS)

    Haneder, Stefan; Attenberger, Ulrike I.; Riffel, Philipp; Henzler, Thomas; Schoenberg, Stefan O.; Michaely, Henrik J.

    2011-01-01

    To compare 3D non-enhanced ECG-gated inflow-dependent MRA (NE-MRA) vs. continuous table movement (CTM) MR-angiography and time-resolved TWIST-MRA in the calf station at 3.0 T in a clinical patient collective. 36 patients (27 male/9 female, 66.1 ± 14.4 years) with PAOD (stage II-IV) underwent during a single MRI: NE-MRA, contrast-enhanced CTM-MRA and TWIST-MRA with a single dose of a gadolinium-based contrast agent. The image quality (IQ) and the degree of stenoses were rated on a four-point scale. Positive (PPV) and negative predictive values (NPV), sensitivity (SS) and specificity (SP) for stenoses detection were calculated for NE-MRA vs. CTM-MRA and vs. TWIST-MRA. Values were obtained for overall graduation of wall changes and for severe stenoses (>70%). With NE-MRA 122/288 segments were not assessable. Compared with CTM-MRA and TWIST-MRA the IQ was significantly inferior (p < 0.0001 to p = 0.0426). CTM-MRA/TWIST-MRA detected stenoses in 44.9%/46.1% of the segments, NE-MRA in 53.5%. SS/NPV of the NE-MRA ranged from 97.8 to 100%. The SP and PPV ranged from 72.7 to 85.5% and 66.7 to 78.2%. Contrast-enhanced MRA techniques are superior to NE-MRA regarding IQ and correct identification of stenoses. If technically successful, NE-MRA is characterised by high NPV and overestimation of the degree of stenoses. (orig.)

  18. The amount of viable and dyssynchronous myocardium is associated with response to cardiac resynchronization therapy: initial clinical results using multiparametric ECG-gated [{sup 18}F]FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, Sebastian; Uebleis, Christopher; Haug, Alexander; Bartenstein, Peter [University of Munich, Department of Nuclear Medicine, Munich (Germany); Schuessler, Franziska; Kaeaeb, Stefan; Estner, Heidi [University of Munich, Medical Department I, Munich (Germany); Van Kriekinge, Serge D.; Germano, Guido [UCLA, Cedars-Sinai Medical Center, Los Angeles and David Geffen School of Medicine, Los Angeles, CA (United States); Hacker, Marcus [Medical University of Vienna, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Theraphy, Vienna (Austria)

    2013-12-15

    There is still a significant amount of patients who do not sufficiently respond to cardiac resynchronization therapy (CRT). Previous studies demonstrated that the amount of dyssynchronous myocardium was predictive of response to CRT. Otherwise, non-response is frequently associated with high amounts of scar tissue. The combination of these parameters might yield a more accurate prediction of response. We hypothesized that the probability of a CRT response increases with the presence of high amounts of ''viable and dyssynchronous'' myocardium. A total of 19 patients (17 male, 61 {+-} 10 years) underwent ECG-gated [{sup 18}F]fluorodeoxyglucose (FDG) myocardial positron emission tomography (PET) before CRT device implantation and were followed for 6 months. Response to CRT was defined as clinical improvement of at least one New York Heart Association (NYHA) class in combination with left ventricular (LV) ejection fraction (EF) improvement of >5 %. Twelve responders (71 %) and seven non-responders (29 %) were identified. For each patient bullseye maps of FDG uptake and phase analysis were calculated (QPS/QGS 2012, Cedars-Sinai, Los Angeles, CA, USA) and fused. Amounts of myocardium representing ''viable and synchronous'', ''scar and synchronous'', viable and dyssynchronous or ''scar and dyssynchronous'' myocardium were quantified by planimetric measurements of the fused bullseye maps. Responders by definition showed significant decrease in NYHA class and significant increase of LVEF. Furthermore, a significantly higher amount of viable and dyssynchronous myocardium was found as compared to non-responders (21 {+-} 13 % vs 6 {+-} 5 %; p < 0.05). Combined assessment of myocardial viability and LV dyssynchrony is feasible using multiparametric [{sup 18}F]FDG PET and could improve conventional response prediction criteria for CRT. (orig.)

  19. 3D non-contrast-enhanced ECG-gated MR angiography of the lower extremities with dual-source radiofrequency transmission at 3.0 T: Intraindividual comparison with contrast-enhanced MR angiography in PAOD patients.

    Science.gov (United States)

    Rasper, Michael; Wildgruber, Moritz; Settles, Marcus; Eckstein, Hans-Henning; Zimmermann, Alexander; Reeps, Christian; Rummeny, Ernst J; Huber, Armin M

    2016-09-01

    To compare prospectively image quality and diagnostic confidence of flow-sensitive 3D turbo spin echo (TSE)-based non-contrast-enhanced MR angiography (NE-MRA) at 3.0 T using dual-source radiofrequency (RF) transmission with contrast-enhanced MRA (CE-MRA) in patients with peripheral arterial occlusive disease (PAOD). After consent was obtained, 35 patients (mean age 69.1 ± 10.6 years) with PAOD stage II-IV underwent NE-MRA followed by CE-MRA. Signal-to-noise ratio and contrast-to-noise ratio were calculated. Subjective image quality was independently assessed by two radiologists and stenosis scoring was performed in 875 arterial segments. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for stenosis classification were calculated using CE-MRA as a reference method. Diagnostic agreement with CE-MRA was evaluated with Cohen's kappa statistics. NE-MRA provided high objective and subjective image quality at all levels of the arterial tree. Sensitivity and specificity for the detection of relevant stenosis was 91 % and 89 %, respectively; the NPV was 96 % and the PPV 78 %. There was good concordance between CE-MRA and NE-MRA in stenosis scoring. 3D electrocardiography (ECG)-gated TSE NE-MRA with patient-adaptive dual-source RF transmission at 3.0 T is a promising alternative for PAOD patients with contraindications for gadolinium-based contrast agents. It offers high sensitivity and NPV values in the detection of clinically relevant arterial stenosis. • Flow-sensitive TSE NE-MRA is a promising technique for PAOD evaluation. • Diagnostic accuracy is comparable to contrast-enhanced MRA. • NE-MRA eliminates the risk of NSF in patients with renal insufficiency. • Costs arising from the use of contrast agents can be avoided.

  20. Gated blood pool imaging in the diagnosis and management of arrhythmia

    International Nuclear Information System (INIS)

    Yamamoto, Shuhei; Kawai, Naoki; Okada, Mitsuhiro; Matsushima, Hideo; Kato, Rinya; Sotobata, Iwao; Tanahashi, Yoshibumi.

    1985-01-01

    The usefulness of multigated cardiac blood pool imaging in evaluating left ventricular function and ventricular activation was studied in patients with cardiac arrhythmias. Subjects consisted of 12 patients with the Wolff-Parkinson-White (WPW) syndrome; 20 with ventricular premature contractions (VPC); 21 with various modes of artificial pacemakers; and two normal controls. 1. Phase analysis was useful in localizing the bypass tract in patients with the WPW syndrome. In four patients with the WPW syndrome and five with VVI pacing, the phase difference between the posterolateral wall of the left ventricle (LV) and the right ventricular apex correlated significantly with the activation time difference between these two regions as assessed by endocardial electrograms (r = 0.94, p < 0.001). 2. Images of VPC were obtained using the bad beat rejection program in an ADAC computer system. The origin of VPCs evaluated by phase image coincided with results of standard 12-lead electrograms. 3. The LV ejection fraction (LVEF) decreased significantly (p < 0.001) after the injection of lidocaine (-3.7 %) or disopyramide (-6.2 %). The percent reduction in LVEF was significantly greater with disopyramide than with lidocaine (-15.1 vs -11.2 %). There was a significant correlation between the percent reduction in LVEF and the disopyramide plasma concentrations (r = -0.62, p < 0.001). 4. The influence of the pacing mode and exercise on LV function was studied in 21 patients with artificial pacemakers. In the VDD and DDD modes, end-diastolic volume (EDV) and cardiac output (CO) decreased after converting to VVI mode. CO increased markedly to approximately 250 % of the control value in the VDD and DDD, and moderately in the VVI and AAI modes during ergometer exercise. (J.P.N.)

  1. Phase analysis of gated blood pool scintigraphy in traumatic myocardial contusion

    International Nuclear Information System (INIS)

    Nishimaki, Hiroshi; Kobayashi, Akiyoshi

    1994-01-01

    It is not easy to make a diagnosis of myocardial contusion following blunt chest trauma, because most patients have many other concurrent injuries with diverse symptoms. The usefulness of phase analysis of gated blood pool scintigraphy (GBPS) for myocardial contusion following blunt chest trauma was evaluated. Thirty-eight patients who had been strongly suspected of having myocardial contusion from clinical symptoms and electrocardiograms underwent phase analysis of GBPS. The results of phase analysis were compared with those of two-dimensional echocardiography (2-D Echo) and CPK-MB fraction measurement in all patients, with those of 201 TlCl myocardial scintigraphy in 35 patients and with those of 99m Tc-pyrophosphate scintigraphy in 10 patients. In 29 patients (76.3%), the results of phase analysis matched those of 2-D Echo. Two patients (5.3%) who were judged as positive by 2-D Echo and as negative by phase analysis had only rupture of the chordae. Only one of two other patients who were judged as negative by 2-D Echo and as positive by phase analysis was judged as positive by 201 TlCl myocardial scintigraphy. The results of both 2-D Echo and phase analysis were not well correlated with those of CPK-MB fraction measurement and 99m Tc pyrophosphate scintigraphy. It is concluded that phase analysis of GBPS, as well as 2-D Echo, is useful for diagnosing myocardial contusion, and that phase analysis is most useful for diagnosing myocardial contusion in patients who cannot be examined by 2-D Echo because of the presence of pneumothorax and/or subcutaneous emphysema in the anterior chest wall. (author)

  2. Phase analysis of gated blood pool scintigraphy in traumatic myocardial contusion

    Energy Technology Data Exchange (ETDEWEB)

    Nishimaki, Hiroshi; Kobayashi, Akiyoshi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine)

    1994-01-01

    It is not easy to make a diagnosis of myocardial contusion following blunt chest trauma, because most patients have many other concurrent injuries with diverse symptoms. The usefulness of phase analysis of gated blood pool scintigraphy (GBPS) for myocardial contusion following blunt chest trauma was evaluated. Thirty-eight patients who had been strongly suspected of having myocardial contusion from clinical symptoms and electrocardiograms underwent phase analysis of GBPS. The results of phase analysis were compared with those of two-dimensional echocardiography (2-D Echo) and CPK-MB fraction measurement in all patients, with those of [sup 201]TlCl myocardial scintigraphy in 35 patients and with those of [sup 99m]Tc-pyrophosphate scintigraphy in 10 patients. In 29 patients (76.3%), the results of phase analysis matched those of 2-D Echo. Two patients (5.3%) who were judged as positive by 2-D Echo and as negative by phase analysis had only rupture of the chordae. Only one of two other patients who were judged as negative by 2-D Echo and as positive by phase analysis was judged as positive by [sup 201]TlCl myocardial scintigraphy. The results of both 2-D Echo and phase analysis were not well correlated with those of CPK-MB fraction measurement and [sup 99m]Tc pyrophosphate scintigraphy. It is concluded that phase analysis of GBPS, as well as 2-D Echo, is useful for diagnosing myocardial contusion, and that phase analysis is most useful for diagnosing myocardial contusion in patients who cannot be examined by 2-D Echo because of the presence of pneumothorax and/or subcutaneous emphysema in the anterior chest wall. (author).

  3. A fundamental study of non-contrast enhanced MR angiography using ECG gated-3D fast spin echo at 3.0 T

    International Nuclear Information System (INIS)

    Nakato, Kengo; Hiai, Yasuhiro; Tomiguchi, Seiji

    2010-01-01

    Contrast-enhanced magnetic resonance angiography (CE-MRA) is frequently performed in body and extremity studies because of its superior ability to detect the vascular stenosis. However, nephrotoxicity of the contrast medium has been emphasized in recent years. Non-contrast MRA using the three-dimensional electrocardiogram-synchronized fast spin echo method (fresh blood imaging (FBI), non-contrast MRA of arteries and veins (NATIVE) and triggered acquisition non contrast enhancement MRA (TRANCE)) is recommended as a substitute for CE-MRA. There are a few reports in the literature that evaluate the detectability of vascular stenosis using non-contrast MRA on 3.0 T MRI. The purpose of this study was to evaluate the detectability of vascular stenosis using non-contrast MRA at 3.0 T with an original vascular phantom. The vascular phantom consisted of silicon tubes. 30% and 70% stenosis of luminal diameter were made. Each silicon tube connected a pump producing a pulsatile flow. A flowing material to was used in this study to show the similarity of the intensity to blood on MRI. MRA without a contrast medium (NATIVE sequence) were performed in the vascular phantom by changing the image matrix, static magnetic field strength and flow velocity. In addition, the NATIVE sequence was used with or without flow compensation. Vascular stenosis was quantitatively estimated by measurement of the signal intensities in non-contrast MRA images. MRA with NATIVE sequence demonstrated an accurate estimation of 30% vascular stenosis at slow flow velocity. However, 30% stenosis was overestimated in cases of high flow velocity. Estimation was improved by using a flow compensation sequence. 70% stenosis was overestimated on MRA with NATIVE sequence. Estimation of 70% stenosis was improved by using a flow compensation sequence. Accurate estimation of vascular stenosis in MRA with a NATIVE sequence is improved by using the flow compensation technique. MRA with NATIVE sequence is considered to

  4. Impact of endothelial dysfunction on left ventricular remodeling after successful primary coronary angioplasty for acute myocardial infarction. Analysis by quantitative ECG-gated SPECT

    International Nuclear Information System (INIS)

    Matsuo, Shinro; Nakae, Ichiro; Matsumoto, Tetsuya; Horie, Minoru

    2006-01-01

    We hypothesized that endothelial cell integrity in the risk area would influence left ventricular remodeling after acute myocardial infarction. Twenty patients (61±8 y.o.) with acute myocardial infarction underwent 99m Tc-tetrofosmin imaging in the sub-acute phase and three months after successful primary angioplasty due to myocardial infarction. All patients were administered angiotensin-converting enzyme inhibitor after revascularization. Cardiac scintigraphies with quantitative gated SPECT were performed at the sub-acute stage and again 3 months after revascularization to evaluate left ventricular (LV) remodeling. The left ventricular ejection fraction (EF) and end-systolic and end-diastolic volume (ESV, EDV) were determined using a quantitative gated SPECT (QGS) program. Three months after myocardial infarction, all patients underwent cardiac catheterization examination with coronary endothelial function testing. Bradykinin (BK) (0.2, 0.6, 2.0 μg/min) was administered via the left coronary artery in a stepwise manner. Coronary blood flow was evaluated by Doppler flow velocity measurement. Patients were divided into two groups by BK-response: a preserved endothelial function group (n=10) and endothelial dysfunction group (n=10). At baseline, both global function and LV systolic and diastolic volumes were similar in both groups. However, LV ejection fraction was significantly improved in the preserved-endothelial function group, compared with that in the endothelial dysfunction group (42±10% to 48±9%, versus 41±4% to 42±13%, p<0.05). LV volumes progressively increased in the endothelial dysfunction group compared to the preserved-endothelial function group (123±45 ml to 128±43 ml, versus 111±47 ml to 109±49 ml, p<0.05). In re-perfused acute myocardial infarction, endothelial function within the risk area plays an important role with left ventricular remodeling after myocardial infarction. (author)

  5. Multiaxial tomography of heart chambers by gated blood-pool emission computed tomography using a rotating gamma camera

    International Nuclear Information System (INIS)

    Tamaki, N.; Mukai, T.; Ishii, Y.; Yonekura, Y.; Yamamoto, K.; Kadota, K.; Kambara, H.; Kawai, C.; Torizuka, K.

    1983-01-01

    Fifteen patients and three volunteers underwent radionuclide blood-pool cardiac studies with electrocardiographic gating. Following conventional planar-gated imaging (anterior and left anterior oblique projections), emission computed tomography (ECT), using a rotating gamma camera, was performed.A series of transaxial tomograms of the cardiac chambers was obtained. The left ventricular short-axis plane, long-axis plane, and four-chamber-view plane were then reorganized; each chamber was visualized separately. Compared to gated planar imaging, this technique showed regional asynergy more clearly in patients with myocardial infarction and demonstrated dilatation of the atria and ventricles more accurately in patients with an atrial septal defect and valvular heart diseases. In addition, when a section of the heart is otained at any angle with gated blood pool ECT, three-dimensional assessment of cardiac chambers in motion is more precise; mutual superimposition becomes unnecessary

  6. Optimum allocation of imaging time and minimum detectable activity in dual isotope blood pool subtraction indium-111 platelet imaging

    International Nuclear Information System (INIS)

    Machac, J.; Horowitz, S.F.; Goldsmith, S.J.; Fuster, V.

    1984-01-01

    Indium-111 labeled platelet imaging is a tool for detection of thrombus formation in vascular spaces. Dual isotope blood pool subtraction may help differentiate focal platelet accumulation from blood pool activity. This study used a computer model to calculate the minimum excess-to-blood pool platelet ratio (EX/BP) and the optimum dual isotope imaging times under varied conditions of lesion size. The model simulated usual human imaging doses of 500 μCi of In-111 platelets and 5mCi of Tc-99m labeled RBCs giving a reference cardiac blood pool region (100cc) of 10000 cpm for Tc-99m and 500 cpm for In-111. The total imaging time was fixed at 20 minutes, while the two isotope imaging times (TIn/TTc) were varied, as were the simulated lesion size (cc) and EX/BP. The relative error of the excess counts was calculated using propagation of error theory. At the critical level of detection, where the excess lesion counts equal 3 times the standard deviation, the optimum TIn/TTc and minimum Ex/BP were determined for each lesion size. For the smallest lesion size (0.1cc), the minimum detectable EX/BP ratio was 1.6, with the best TIn/TTC ratio of 18/2 minutes, and for large lesions, an EX/BP of 0.1, with a TIn/TTc of 16/4. This model provides an estimate of the sensitivity and optimizes imaging times in dual isotope subtraction platelet imaging. The model is adaptable to varying isotope doses, total imaging times and lesion size. This information will be helpful in future in- vivo imaging studies of intravascular thrombi in humans

  7. Evaluation of the vascular state of hepatic tumor with radioisotope angiography and blood pool scintigraphies (early and delayed)

    International Nuclear Information System (INIS)

    Aburano, Tamio; Tonami, Norihisa; Hisada, Kinichi

    1976-01-01

    Combined radioisotope examinations of hepatic tumors have been performed using α 1 -fetoprotein radioimmunoassay, radioisotope angiography of the liver, and some tumor positive imaging scintigraphies. However, with these methods, it is frequently impossible to differentiate metastatic cancers from benign focal lesions. Radioisotope angiography of the liver, and both early (5 min later)- and delayed (4 hours later) blood pool scintigraphies of the liver were done continuously after 10mCi of sup(99m)Tc-albumin intravenous injection, in cases of clearcut focal lesions on sup(99m)Tc-colloid liver scan. The relationships among these findings were examined. Four of seven cases with hepatoma and two of nine cases with metastatic cancer which had showed hypervascular findings on radioisotope angiogram showed clear blood pool activities in the area of focal defects on sup(99m)Tc-colloid scan although less than liver. On the other hand, none of hypovascular tumors on radioisotope angiogram showed blood pool activities. However, four hours later, in most malignant lesions, the lesion to liver activity ratio calculated from data processing system showed a much higher value than the ratio obtained 5 min later after injection, although two cases with benign focal lesions did not show such sequential change. The sequential evaluation of the vascular state of a hepatic tumor using radioisotope angiography and early-and delayed blood pool scintigraphies was supposed to be extremely useful for the elucidation of the nature of focal hepatic lesions on sup(99m)Tc-colloid scan, especially in differentiating hypovascular malignant- and benign lesions. (auth.)

  8. Quantification of wall motion and phase of contraction in tomographic gated blood pool studies using length-based Fourier analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Kenichi; Bunko, Hisashi; Taki, Junichi; Nambu, Ichiro; Shiire, Yasushi; Tonami, Norihisa; Hisada, Kinichi; Tada, Akira; Kojima, Kazuhkio

    1985-03-01

    Length-based Fourier analysis, a new method for quantification of wall motion and timing of contraction, was applied to tomographic gated blood pool study. Two parameters, percent-length shortening (%LS) and length-based phase were calculated based on the time-length curves from a center to ventricular edges, and compared with the count-based method. In mathematical models for tomographic gated blood pool images, the severity of asynergy was easily determined by length-based method, and the accuracy of the parameters was good. As to the setting of the center, fixed center provided more reliable parameters than the method using movable center, i.e., when a center of gravity was determined in each frame. By length-based Fourier analysis, quantification of wall motion was easily performed, and the initial inward movement caused by the accessory conduction pathway was assessed in patients with Wolff-Parkinson-White syndrome. Length-based approach was considered to be reasonable and effective because the movements of the ventricular edges are essential in tomographic gated blood pool images.

  9. Quantification of wall motion and phase of contraction in tomographic gated blood pool studies using length-based Fourier analysis

    International Nuclear Information System (INIS)

    Nakajima, Kenichi; Bunko, Hisashi; Taki, Junichi; Nambu, Ichiro; Shiire, Yasushi; Tonami, Norihisa; Hisada, Kinichi; Tada, Akira; Kojima, Kazuhiko.

    1985-01-01

    Length-based Fourier analysis, a new method for quantification of wall motion and timing of contraction, was applied to tomographic gated blood pool study. Two parameters, percent-length shortening (%LS) and length-based phase were calculated based on the time-length curves from a center to ventricular edges, and compared with the count-based method. In mathematical models for tomographic gated blood pool images, the severity of asynergy was easily determined by length-based method, and the accuracy of the parameters was good. As to the setting of the center, fixed center provided more reliable parameters than the method using movable center, i.e., when a center of gravity was determined in each frame. By length-based Fourier analysis, quantification of wall motion was easily performed, and the initial inward movement caused by the accessory conduction pathway was assessed in patients with Wolff-Parkinson-White syndrome. Length-based approach was considered to be reasonable and effective because the movements of the ventricular edges are essential in tomographic gated blood pool images. (author)

  10. Evaluation of latent cardiac disease in diabetic patients with Tl-201 exercise myocardial scintigram and blood pool scintigram

    International Nuclear Information System (INIS)

    Miyashita, Takeo; Kasai, Ryutaro; Ikebe, Nobuhiko; Nagai, Yoshikazu; Yamasawa, Ikuhiro; Ibukiyama, Chiharu; Notoya, Yoko

    1990-01-01

    To find latent heart disease in diabetic patients, 142 diabetic patients were divided into 4 groups: (1) no hypertension and normal ECG (DM group); (2) hypertension recognized clinically (HT group); (3) myocardial damage on ECG (MD group); (4) group associated with the previous 2 (HT+MD group). In all groups Tl-201 exercise myocardial scintigrams and blood pool scintigrams were taken for comparative analysis. Positive rates of SPECT were 27.7% (23/83) in the DM group, 30.0% (9/30) in the HT group, 50.0% (6/12) in the MD group, and 70.6% (12/17) in the HT+MD group. The rate in the HT+MD group was significantly higher than in that of the DM and HT groups (p<0.001, p<0.01). Blood pool scintigrams revealed that in the HT+MD group, as compared with the normal control group, both 1/3 FF and PFR were significantly depressed, in addition to significant TPF prolongation in the former (p<0.001, p<0.05, p<0.05). These findings suggest that in diabetic patients hypertension and myocardial damage would lead to a high incidence of abnormality in SPECT and left ventricular rapid filling dysfunction. This indicate a high incidence of latent cardiac disease which can be recognized in diabetic patients by stress myocardial and blood pool scintigrams. (author)

  11. Sensitivity of nested-PCR for plasmodium detection in pooled whole blood samples and its usefulness to blood donor screening in endemic areas.

    Science.gov (United States)

    de Freitas, Daniel Roberto Coradi; Gomes, Luciano Teixeira; Fontes, Cor Jesus F; Tauil, Pedro Luiz; Pang, Lorrin W; Duarte, Elisabeth Carmen

    2014-04-01

    Transfusion-transmitted malaria is a severe disease with high fatality rate. Most Brazilian blood banks in the Amazon region perform malaria screening using microscopic examination (thick smears). Since low parasite concentrations are expected in asymptomatic blood donors a high sensitivity test should be used for donor screening. This study determined the sensitivity of a nested-PCR for plasmodium detection in pooled samples. We performed a one-stage criterion validation study with 21 positive samples pooled with samples from ten negative volunteer until three different concentrations were reached (0.33; 0.25; 0.20 parasites/μL - p/μL). Nested PCR was performed as described by Snounou et al. (1993). Sensitivities (and confidence intervals) were determined by stratum of final parasite concentration on the pooled samples. All samples with parasitemia values of 0.33 and 0.25 p/μL had 100% sensitivity (95%CI=86.3-100). One negative result was obtained from a sample with 0.20 p/μL sensitivity=95.2% (95%CI=76.2-99.9). Compared to parasitemia detectable under ideal conditions of thick smear, this nested-PCR in pooled sample was able to detect 40 times more parasites per microliter. Nested-PCR in pooled samples should be considered as a high sensitive alternative to thick smear for donor screening in blood banks at endemic regions. Local authorities need to assess cost:benefit advantages of this method compared to alternatives. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Assessment of cardiac blood pool imaging in patients with left ventricular outflow tract stenosis

    International Nuclear Information System (INIS)

    Nakamura, Yutaka; Ono, Yasuo; Kohata, Tohru; Tsubata, Shinichi; Kamiya, Tetsuroh.

    1993-01-01

    We performed cardiac blood pool imagings with Tc-99m at rest and during supine ergometer exercise to evaluate left ventricular performance in 14 patients with left ventricular outflow tract stenosis. All catheterized patients were divided into two subgroups: 8 patients with peak systolic left ventricular to descending aortic pressure gradients of less than 50 mmHg (LPG group) and 6 patients with peak systolic gradients of more than 50 mmHg (HPG group). Control group included 10 patients without stenotic coronary lesions after Kawasaki disease. Left ventricular ejection fraction (LVEF) was obtained as systolic index; both filling fraction during the first third of diastole (1/3FF) and mean filling rate during the first third of diastole (1/3FR mean) were obtained as diastolic indices. None of the patients had abnormal findings on 201 Tl imaging. LVEF at rest in HPG group was significantly higher than those in control group, but LVEF in HPG group did not increase after exercise. It increased significantly in control group and LPG group. 1/3 FF in HPG group was significantly lower not only at rest but also during exercise. 1/3 FR mean at rest was not different significantly among the 3 groups. However, 1/3FR mean during exercise in LPG group was significantly lower; and 1/3 FR mean during exercise was significantly lower in HPG group than LPG group. The ratio of left ventricular muscular mass to left ventricular end-diastolic volume (M/V) calculated from left ventricular cineangiograms was different significantly among the 3 groups. The M/V ratio showed a correlation with LVEF and 1/3 FF both at rest and during exercise. These results would indicate that systolic function was impaired on exercise in severe left ventricular outflow tract stenosis and diastolic function was impaired on exercise in mild and severe left ventricular outflow tract stenosis. This may correlate with left ventricular hypertrophy and interaction of systolic function. (author)

  13. Surveillance study for creating the national clinical database relating to ECG-gated myocardial perfusion SPECT of asymptomatic ischemic heart disease in patients with type-2 diabetes mellitus. J-ACCESS 2 study design

    International Nuclear Information System (INIS)

    Kusuoka, Hideo; Yamasaki, Yoshimitsu; Izumi, Tohru; Kashiwagi, Atsunori; Kawamori, Ryuzo; Shimamoto, Kazuaki; Yamada, Nobuhiro; Nishimura, Tsunehiko

    2008-01-01

    Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon emission computed tomography (SPECT) of ischemic heart disease. Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will be followed for 3 years, stratified by patients' clinical background and SPECT findings. A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2±0.4 years, mean±standard error of the mean (SEM)) and 261 women (age 67.8±0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension (82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis, and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%), and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received 99m Tc-tetrofosmin at an initial dosage of 200-300 MBq (mean 331±3 MBq) followed by a second dosage of 700-800 MBq (mean 748±8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were

  14. In Vitro Absorption of Atmospheric Carbon Monoxide and Hydrogen Cyanide in Undisturbed Pooled Blood

    Science.gov (United States)

    2012-09-01

    Biological samples from victims of aircraft accidents are analyzed for carboxyhemoglobin (COHb) and cyanide ion : (CN) in blood. Such victims quite often suffer large open wounds near the autopsy blood collection sites. Many : aircraft crashes resu...

  15. [Single-donor (apheresis) platelets and pooled whole-blood-derived platelets--significance and assessment of both blood products].

    Science.gov (United States)

    Hitzler, Walter E

    2014-01-01

    The transfusion efficacy of ATK, which contain fully functional platelets, is beyond all doubt. The equivalence of ATK and PTK has been subject of many studies. Some of those studies show the superiority of ATK's, while others do not, but there have been no studies that demonstrated a superiority of PTK's. The superiority of platelets stored in plasma and in third generation additive solution was demonstrated in clinical studies; therefore, it cannot be said that all the platelet concentrates on the German market are equivalent in efficacy. Of decisive importance, above all, is the risk of transfusion-transmitted infections with known pathogens, or those not yet discovered. This risk is different for ATK compared to PTK. Taking this difference in risk and the difference in donor exposure of transfused patients into account, it can definitely be said that ATK and PTK are not equivalent. In 2012, the Robert-Koch-Institute (RKI) published a mathematical risk model for different platelet concentrates and assessed the risk of transmitting known pathogens such as HIV, HCV, and HBV. The risk was higher for PTK compared to ATK. The relative risks for PTK derived from 4BCs were 2.2 (95%--CI: 2.1-2.4) for HIV, 2.7 (95%--CI: 2.5-3.0) for HCV, and 2.2 (95%--CI: 2.8-3.7) for HBV. At the present time, these are the relative risks of transfusion-transmitted infections with the traditional pathogens for PTK compared to ATK. In addition to the RKI assessed risks, there is the theoretical risk of a new, unknown agent, transmitted through blood exposure. The magnitude of this risk is hardly predictable for PTK. The experience gathered so far, especially in the last three decades, with the emergence of HIV, prions, and West Nil virus, shows that the biological nature of a next transfusion-transmissible infectious agent cannot be predictable. This agent, if we think at a conventional sexually transmissible agent with nucleic acid and long latent period, would spread first in areas with

  16. Half a decade of mini-pool nucleic acid testing: Cost-effective way for improving blood safety in India

    Directory of Open Access Journals (Sweden)

    Shivaram Chandrashekar

    2014-01-01

    Full Text Available Background and Objectives: It is well established that Nucleic acid testing (NAT reduces window phase of transfusion transmissible infections (TTI and helps improve blood safety. NAT testing can be done individually or in pools. The objectives of this study were to determine the utility, feasibility and cost effectiveness of an in-house minipool-NAT(MP-NAT. Materials and Methods: Blood donors were screened by history, tested by ELISA and sero-negative samples were subjected to an in-house NAT by using reverse transcriptase-polymerase chain reaction (RT-PCR. Testing was done in mini-pools of size eight (8. Positive pools were repeated with individual samples. Results: During the study period of Oct 2005-Sept 2010 (5 years all blood donors (n=53729 were screened by ELISA. Of which 469 (0.87% were positive for HIV-1, HBV or HCV. Sero-negative samples (n=53260 were screened by in-house MP-NAT. HIV-NAT yield was 1/53260 (n=1 and HBV NAT yield (n=2 was 1/26630. Conclusion: NAT yield was lower than other India studies possibly due to the lower sero-reactivity amongst our donors. Nevertheless it intercepted 9 lives including the components prepared. The in-house assay met our objective of improving blood safety at nominal cost and showed that it is feasible to set up small molecular biology units in medium-large sized blood banks and deliver blood within 24-48 hours. The utility of NAT (NAT yield will vary based on the donor population, the type of serological test used, the nature of kit employed and the sensitivity of NAT test used. The limitations of our in-house MP-NAT consisted of stringent sample preparation requirements, with labor and time involved. The benefits of our MP-NAT were that it acted as a second level of check for ELISA tests, was relatively inexpensive compared to ID-NAT and did not need sophisticated equipment.

  17. In Vitro Absorption of Atmospheric Carbon Monoxide and Hydrogen Cyanide in Undisturbed Pooled Blood

    Science.gov (United States)

    2012-09-01

    are analyzed for carboxyhemoglobin (COHb) and cyanide ion (CN¯) in blood. Such victims quite often suffer large open wounds near the autopsy blood...could.lead.investigators.to.erroneously.conclude.that.the. presence.of. carboxyhemoglobin . (COHb).and.cyanide. ion.(CN

  18. Namibia's transition from whole blood-derived pooled platelets to single-donor apheresis platelet collections

    NARCIS (Netherlands)

    Pitman, John P.; Basavaraju, Sridhar V.; Shiraishi, Ray W.; Wilkinson, Robert; von Finckenstein, Bjorn; Lowrance, David W.; Marfin, Anthony A.; Postma, Maarten; Mataranyika, Mary; Smit Sibinga, Cees Th.

    BACKGROUNDFew African countries separate blood donations into components; however, demand for platelets (PLTs) is increasing as regional capacity to treat causes of thrombocytopenia, including chemotherapy, increases. Namibia introduced single-donor apheresis PLT collections in 2007 to increase PLT

  19. Relaxivity of blood pool contrast agent depends on the host tissue as suggested by semianalytical simulations

    DEFF Research Database (Denmark)

    Jensen, Birgitte Fuglsang; Østergaard, Leif; Kiselev, Valerij G

    Concentration of MRI contrast agents (CA) is commonly determined indirectly using their relaxation effect. In quantitative perfusion studies, the change in the relaxation following a bolus passage is converted into concentrations assuming identical relaxivities for tissue and blood. Simulations...

  20. Jugular venous pooling during lowering of the head affects blood pressure of the anesthetized giraffe

    DEFF Research Database (Denmark)

    Brøndum, E.; Hasenkam, John Michael; Secher, Niels H.

    2009-01-01

    How blood flow and pressure to the giraffe's brain are regulated when drinking remains debated. We measured simultaneous blood flow, pressure, and cross-sectional area in the carotid artery and jugular vein of five anesthetized and spontaneously breathing giraffes. The giraffes were suspended...... veins collapsed and blood was returned to the central circulation, and CVP and cardiac output were restored. The results demonstrate that in the upright-positioned, anesthetized giraffe cerebral blood flow is governed by arterial pressure without support of a siphon mechanism and that when the head...... in the upright position so that we could lower the head. In the upright position, mean arterial pressure (MAP) was 193 +/- 11 mmHg (mean +/- SE), carotid flow was 0.7 +/- 0.2 l/min, and carotid cross-sectional area was 0.85 +/- 0.04 cm(2). Central venous pressure (CVP) was 4 +/- 2 mmHg, jugular flow was 0...

  1. Job strain and blood pressure in employed men and women: a pooled analysis of four northern italian population samples.

    Science.gov (United States)

    Cesana, Giancarlo; Sega, Roberto; Ferrario, Marco; Chiodini, Paolo; Corrao, Giovanni; Mancia, Giuseppe

    2003-01-01

    The extent to which psychosocial stress concurs to raise blood pressure is still uncertain. Here the association between job strain and office blood pressure in a pooled analysis of four population samples from northern Italy is assessed. Four surveys assessing prevalence of major coronary risk factors were performed in 1986, 1990, 1991, and 1993 in area "Brianza" (Milan), a World Health Organization-MONItoring cardiovascular disease (WHO-MONICA) Project collaborating center. Ten year age- and gender-stratified independent samples were randomly recruited from the 25- to 64-year-old residents. The methods used to assess coronary risk factors strictly adhered to the MONICA manual, were kept constant, and underwent internal and external quality controls. Job strain was investigated through the administration to employed participants of a questionnaire derived from the Karasek model, assessing job demand/control latitude. Analysis was restricted to 25- to 54-year-old participants, untreated for hypertension (1799 men and 1010 women). Among men, there was a 3 mm Hg increase of systolic blood pressure (pjob categories. This difference was independent from age, education, body mass index, alcohol intake, smoking habits, leisure time physical activity, and survey. No relevant differences among job strain categories were found in women and for diastolic blood pressure in both gender groups. These results carried out on a large population-based sample confirm previous findings obtained adopting ambulatory blood pressure measurements in more restricted samples of population or patients. Further research is needed to clarify the relationship between perceived work stress and blood pressure in women.

  2. Jugular venous pooling during lowering of the head affects blood pressure of the anesthetized giraffe.

    Science.gov (United States)

    Brøndum, E; Hasenkam, J M; Secher, N H; Bertelsen, M F; Grøndahl, C; Petersen, K K; Buhl, R; Aalkjaer, C; Baandrup, U; Nygaard, H; Smerup, M; Stegmann, F; Sloth, E; Ostergaard, K H; Nissen, P; Runge, M; Pitsillides, K; Wang, T

    2009-10-01

    How blood flow and pressure to the giraffe's brain are regulated when drinking remains debated. We measured simultaneous blood flow, pressure, and cross-sectional area in the carotid artery and jugular vein of five anesthetized and spontaneously breathing giraffes. The giraffes were suspended in the upright position so that we could lower the head. In the upright position, mean arterial pressure (MAP) was 193 +/- 11 mmHg (mean +/- SE), carotid flow was 0.7 +/- 0.2 l/min, and carotid cross-sectional area was 0.85 +/- 0.04 cm(2). Central venous pressure (CVP) was 4 +/- 2 mmHg, jugular flow was 0.7 +/- 0.2 l/min, and jugular cross-sectional area was 0.14 +/- 0.04 cm(2) (n = 4). Carotid arterial and jugular venous pressures at head level were 118 +/- 9 and -7 +/- 4 mmHg, respectively. When the head was lowered, MAP decreased to 131 +/- 13 mmHg, while carotid cross-sectional area and flow remained unchanged. Cardiac output was reduced by 30%, CVP decreased to -1 +/- 2 mmHg (P blood in the veins. When the head was raised, the jugular veins collapsed and blood was returned to the central circulation, and CVP and cardiac output were restored. The results demonstrate that in the upright-positioned, anesthetized giraffe cerebral blood flow is governed by arterial pressure without support of a siphon mechanism and that when the head is lowered, blood accumulates in the vein, affecting MAP.

  3. A new 99mTc-red blood cell labeling procedure for cardiac blood pool imaging: Clinical results

    International Nuclear Information System (INIS)

    Kelbaek, H.; Buelow, K.; Aldershvile, J.; Moegelyang, J.; Nielsen, S.L.; Copenhagen Univ.

    1989-01-01

    The first clinical results of a new 99m Tc-red blood cell labeling procedure avoiding cell centrifugation are presented. One ml heparinized blood samples were incubated with small amounts of a stannous kit. By titration studies, ideal quantities of sodium hypochlorite for oxidation of extracellular tin and of EDTA as stabilizer of the label were found. The Cl - concentration and pH of the labeled blood were acceptable, and EDTA increased labeling yield and stability determined in vitro by a few percent. The new procedure gave a slightly higher labeling yield than a current technique using centrifugation of cells. Labeling efficiency expressed as cell bound/total activity was 96.6%±1.3% in healthy subjects and 95.5%±2.2% in cardiac patients and remained high for 2 h after reinjection. The biological halflife of labeled cells following the new procedure was 11-12 h rendering it suitable for serial determinations of radionuclide cardiography. (orig.)

  4. High spatial resolution magnetic resonance imaging of experimental cerebral venous thrombosis with a blood pool contrast agent

    International Nuclear Information System (INIS)

    Spuentrup, E.; Wiethoff, A.J.; Parsons, E.C.; Spangenberg, P.; Stracke, C.P.

    2010-01-01

    Purpose: The purpose of this study was to investigate the feasibility of clot visualization in small sinus and cortical veins with contrast enhanced MRA in a cerebral venous thrombosis animal model using a blood pool contrast agent, Gadofosveset, and high spatial resolution imaging. Material and methods: For induction of cerebral venous thrombosis a recently developed combined interventional and microsurgical model was used. Cerebral sinus and cortical vein thrombosis was induced in six pigs. Two further pigs died during the procedure. Standard structural, time-of-flight- and phase contrast-angiograms were followed by fast time resolved high resolution 3D MRA (4D MRA) and subsequent high spatial resolution 3D MRA in the equilibrium phase with and without addition of parallel imaging. Visualization of the clots using the different sequences was subjectively compared and contrast-to-noise ratio (CNR) was assessed. Results: In the remaining six animals the procedure and MR-imaging protocol including administration of Gadofosveset was successfully completed. The 3D high resolution MRA in the equilibrium phase without the addition of parallel imaging was superior to all the other applied MR measurement techniques in terms of visualization of the clots. Only applying this sequence bridging vein thromboses were also seen as a small filling defect with a high CNR of >18. Conclusion: Only the non-accelerated high spatial resolution 3D MRA in the equilibrium in conjunction with the blood pool agent Gadofosveset allows for high-contrast visualization of very small clots in the cerebral sinus and cortical veins. Statement clinical impact: Detection of cortical vein thrombosis is of high clinical impact. Conventional MRI sequences often fail to visualize the clot. We could demonstrate that, in contrast to conventional sequences, with high spatial resolution 3D MRA in the equilibrium in conjunction with the blood pool agent Gadofosveset very small clots in the cerebral sinus and

  5. Use of pooled blood plasmas in the assessment of fouling resistance

    Czech Academy of Sciences Publication Activity Database

    de los Santos Pereira, Andres; Rodriguez-Emmenegger, Cesar; Surman, František; Riedel, Tomáš; Bologna Alles, A.; Brynda, Eduard

    2014-01-01

    Roč. 4, č. 5 (2014), s. 2318-2321 ISSN 2046-2069 R&D Projects: GA MŠk EE2.3.30.0029; GA ČR GAP106/12/1451; GA ČR GAP205/12/1702; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61389013 Keywords : blood plasma * fouling * biomaterials Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.840, year: 2014

  6. MRT of experimental liver abscesses - comparison of a new blood pool contrast agent with gadolinium-DTPA

    International Nuclear Information System (INIS)

    Dick, A.; Adam, G.; Spuentrup, E.; Prescher, A.; Muehler, A.; Guenther, R.W.

    1996-01-01

    Purpose: In an experimental pyogenic liver abscess model, the signal intensities were compared intraindividually and interindividually after the application of a new blood pool contrast agent, 24-gadolinium-DTPA (diethylenetriamine-pentaacetic acid) cascade polymer, and after the application of gadopentetate dimeglumine. Methods: In 20 rabbits with experimentally induced liver abscesses, the relative signal intensities of the liver, abscess centre, abscess wall and portal vein were assessed before and between 30 seconds and 60 minutes after injection of a 25 μmol/kg dose of gadolinium polymer and of 100 μmol/kg of gadolinium-DTPA, respectively. Measurements were performed at 1.5 Tesla, using a head coil and a Flash-2-D sequence. Results: The interindividual comparison (unpaired T-test, p [de

  7. The evaluation of right ventricular performance using krypton-81m multiple-gated equilibrium cardiac blood pool scintigraphy

    International Nuclear Information System (INIS)

    Hosoi, Tsutomu

    1993-01-01

    Technetium-99m first pass angiography and multiple-gated equilibrium blood pool scintigraphy have been used for evaluating right ventricular performance, but both techniques have several methodologic limitations. The activity of kr-81m is exhaled during its transit through the lungs and residual activity in the left heart is negligible. Therefore, right heart study can be performed in the right anterior oblique position with optimal separation between the right ventricle and the right atrium. Thus, the author assessed right ventricular function using Kr-81m multiple-gated equilibrium cardiac blood pool scintigraphy in 40 patients with old myocardial infarction and 9 normal subjects. The patient group included 11 cases of inferior infarction with a significant stenosing lesion proximal to the origin of the right ventricular branch of the right coronary artery (group I), 11 cases of inferior infarction without a significant lesion in the proximal portion of the right coronary artery (group II) and 18 cases of anterior wall infarction (group III). The right ventricular ejection fraction (EF) was 45.6±9.8% in group I, 56.6±5.7% in group II, 55.6±4.4% in group III and 53.7±3.2% in the 9 normal subjects. There were no statistically significant differences among these 4 groups. However, right ventricular EF was significantly reduced in 5 group I patients who had hemodynamic evidence of right ventricular infarction (39.4±9.5%, P<0.01 vs group II, group III and normal subjects). No significant correlation was found between right and left ventricular EF or between right ventricular EF and wall motion abnormality of the interventricular septum. (author)

  8. Determination of right ventricular ejection fraction from reprojected gated blood pool SPET: comparison with first-pass ventriculography

    International Nuclear Information System (INIS)

    Bartlett, M.L.; Seaton, D.; McEwan, L.; Fong, W.

    2001-01-01

    Gated blood pool (GBP) studies are widely available and relatively inexpensive. We have previously published a simple and convenient method for measuring left ventricle ejection fraction (EF) with increased accuracy from single-photon emission tomography (SPET) GBP scans. This paper describes an extension of this method by which right ventricular EF may also be measured. Gated SPET images of the blood pool are acquired and re-oriented in short-axis slices. Counts from the left ventricle are excluded from the short-axis slices, which are then reprojected to give horizontal long-axis images. Time-activity curves are generated from each pixel around the right ventricle, and an image is created with non-ventricular pixels ''greyed out''. This image is used as a guide in drawing regions of interest around the right ventricle on the end-diastolic and end-systolic long-axis images. In 28 patients, first-pass ventriculography studies were acquired followed by SPET GBP scans. The first-pass images were analysed a total of four times by two observers and the SPET images were analysed three times each by two observers. The agreement between the two techniques was good, with a correlation coefficient of 0.72 and a mean absolute difference between first-pass and reprojected SPET EFs of 4.8 EF units. Only four of the 28 patients had a difference of greater than 8 EF units. Variability was also excellent for SPET right ventricular EF values. Intra-observer variability was significantly lower for SPET than for first-pass EFs: standard error of the estimate (SEE)=5.1 and 7.3 EF units, respectively (P<0.05). Inter-observer variability was comparable in the two techniques (SEE=5.2 and 6.9 EF units for SPET and first-pass ventriculography, respectively). (orig.)

  9. Comparison of early thallium-201 scintigraphy and gated blood pool imaging for predicting mortality in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    Becker, L.C.; Silverman, K.J.; Bulkley, B.H.; Kallman, C.H.; Mellits, E.D.; Weisfeldt, M.

    1983-01-01

    The extent of abnormality in early thallium-201 and gated cardiac blood pool scintigrams has been reported to be useful for predicting mortality in patients with acute myocardial infarction (AMI). To compare the two techniques, 91 patients admitted consecutively with evident or strongly suspected AMI underwent both imaging studies within 15 hours of the onset of symptoms. Patients with pulmonary edema or shock were excluded. AMI developed in 84% of patients, and 6-month mortality for the entire group was 16%. A thallium defect score of 7.0 or greater identified a subgroup of 14 patients with 64% 6-month mortality rate. Similarly, a left ventricular ejection fraction of 35% or less identified a high-risk subgroup of 10 patients with a 6-month mortality of 60%. Mortality in the remaining patients was 8% for thallium score less than 7 and 11% for ejection fraction greater than 35%. The mortality rate was highest among patients who had concordant high-risk scintigrams (five of six, 83%), lowest in those with concordant low-risk studies (five of 64, 8%) and intermediate in those with discordant results (four of 11, 36%). Of a number of clinical variables, only the appearance of Q waves, peak creatine kinase greater than 1000 IU/I, and history of infarction were significantly associated with mortality. High-risk thallium or blood pool scintigraphic results were significantly more predictive and a thallium score of 7 or greater was more sensitive for detecting nonsurvivors than ejection fraction 35% or less at a similar level of specificity

  10. Relaxivity of blood pool contrast agent depends on the host tissue as suggested by semianalytical simulations

    DEFF Research Database (Denmark)

    Kjølby, Birgitte Fuglsang; Østergaard, Leif; Kiselev, Valerij

    Concentration of magnetic resonance imaging (MRI) contrast agents (CA) cannot be measured directly and is commonly determined indirectly using their relaxation effect. This requires knowledge of the relaxivity of the used CA. Quantitative perfusion studies involve measurement of CA concentration...... studies (3,4) as demonstrated in (5). It was previously found (6) that the perfusion measurements using dynamic susceptibility contrast inherently overestimate cerebral blood flow and volume. In view of the present result, this is attributed to the significant difference in the relaxivity of the CA...

  11. Scintigraphic diagnosis of gastrointestinal bleeding with 99μTc-labeled blood-pool agents

    International Nuclear Information System (INIS)

    Miskowiak, J.; Nielsen, S.; Munck, O.

    1981-01-01

    Abdominal scintigraphy with 99 μTc-labeled albumin or red blood cells was used in 68 patients to localize gastrointestinal bleeding or confirm that it had stopped. Acute, active bleeding was identified in 33 patients; characteristic patterns of bleeding from the stomach, biliary passages, small intestine, and colon are shown. Sensitivity was 0.86 (95% confidence limits, 0.57-0.98) and specificity was 1.0 (95% confidence limits, 0.82-1.0) in 33 patients who had scintigraphy and endoscopy performed in succession. Abdominal scintigraphy appears to be a valuable supplement to conventional diagnostic methods. In upper gastrointestinal bleeding, scintigraphy should be considered when endoscopy fails. In lower intestinal bleeding, scintigraphy should be the method of choice

  12. Scintigraphic diagnosis of gastrointestinal bleeding with 99mTc-labeled blood-pool agents

    International Nuclear Information System (INIS)

    Miskowiak, J.; Nielsen, S.L.; Munck, O.

    1981-01-01

    Abdominal scintigraphy with 99 mTc-labeled albumin or red blood cells was used in 68 patients to localize gastrointestinal bleeding or confirm that it had stopped. Acute, active bleeding was identified in 33 patients; characteristic patterns of bleeding from the stomach, biliary passages, small intestine, and colon are shown. Sensitivity was 0.86 (95% confidence limits, 0.57-0.98) and specificity was 1.0 (95% confidence limits, 0.82-1.0) in 33 patients who had scintigraphy and endoscopy performed in succession. Abdominal scintigraphy appears to be a valuable supplement to conventional diagnostic methods. In upper gastrointestinal bleeding, scintigraphy should be considered when endoscopy fails. In lower intestinal bleeding, scintigraphy should be the method of choice

  13. Pooled HIV-1 viral load testing using dried blood spots to reduce the cost of monitoring antiretroviral treatment in a resource-limited setting.

    Science.gov (United States)

    Pannus, Pieter; Fajardo, Emmanuel; Metcalf, Carol; Coulborn, Rebecca M; Durán, Laura T; Bygrave, Helen; Ellman, Tom; Garone, Daniela; Murowa, Michael; Mwenda, Reuben; Reid, Tony; Preiser, Wolfgang

    2013-10-01

    Rollout of routine HIV-1 viral load monitoring is hampered by high costs and logistical difficulties associated with sample collection and transport. New strategies are needed to overcome these constraints. Dried blood spots from finger pricks have been shown to be more practical than the use of plasma specimens, and pooling strategies using plasma specimens have been demonstrated to be an efficient method to reduce costs. This study found that combination of finger-prick dried blood spots and a pooling strategy is a feasible and efficient option to reduce costs, while maintaining accuracy in the context of a district hospital in Malawi.

  14. A Giant Hepatic Hemangioma Complicated by Kasabach-Merritt Syndrome: Findings of Tc-99m RBC Scintigraphy and SPECT Including a Total Body Blood Pool Imaging Study

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Myung Hee; Jeong, Hwan Jeong; Lim, Seok Tae; Kim, Dong Wook; Yim, Chang Yeol [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    2009-02-15

    Kasabach-Merritt syndrome (KMS) consists of thrombocytopenia, microangiopathic hemolytic anemia, and localized consumption coagulopathy that develops within vascular hemangioma. This syndrome may also be associated with occult hemangiomas located at various sites. Tc-99m RBC scintigraphy and SPECT have proven to be reliable for confirming or excluding hemangioma. Total body blood pool imaging study during the scintigraphy also provides a means of screening for occult lesions. The authors report the case of a 29-year-old man who presented with a giant hepatic hemangioma complicated by KMS, and underwent Tc-99m RBC scintigraphy and SPECT including a total body blood pool imaging study.

  15. Assessing the performance of multiplexed tandem PCR for the diagnosis of pathogenic genotypes of Theileria orientalis using pooled blood samples from cattle.

    Science.gov (United States)

    Gebrekidan, Hagos; Gasser, Robin B; Stevenson, Mark A; McGrath, Sean; Jabbar, Abdul

    2017-02-01

    Oriental theileriosis caused by multiple genotypes of Theileria orientalis is an important tick-borne disease of bovines. Here, we assessed the performance of an established multiplexed tandem PCR (MT-PCR) for the diagnosis of the two recognized, pathogenic genotypes (chitose and ikeda) of T. orientalis in cattle using pooled blood samples. We used a total of 265 cattle blood samples, which were divided into two groups according to previous MT-PCR results for individual samples. Samples in group 1 (n = 155) were from a herd with a relatively high prevalence of T. orientalis infection; and those in group 2 (n = 110) were from four herds with a low prevalence. For group 1, 31 and 15 batches of five- and ten-pooled samples (selected at random), respectively, were formed. For group 2, 22 and 11 batches of five- and ten-pooled samples (selected at random), respectively, were formed. DNAs from individual pooled samples in each batch and group were then tested by MT-PCR. For group 1, the apparent prevalences estimated using the 31 batches of five-pooled samples (97%) and 15 batches of ten-pooled samples (100%) were significantly higher compared with individual samples (75%). For group 2, higher apparent prevalences (9% and 36%) were also recorded for the 22 and 11 batches of pooled samples, respectively, compared with individual samples (7%). Overall, the average infection intensity recorded for the genotypes of chitose and ikeda were considerably lower in pooled compared with individual samples. The diagnostic specificities of MT-PCR were estimated at 95% and 94%, respectively, when batches of five- and ten-pooled samples were tested, and 94% for individual samples. The diagnostic sensitivity of this assay was estimated at 98% same for all individual, five- and ten-pooled samples. This study shows that screening batches of five- and ten-pooled blood samples from cattle herds are similar to those obtained for individual samples, and, importantly, that the reduced cost

  16. Radionuclide angiography and blood pool imaging to assess skin ulcer healing prognosis in patients with peripheral vascular disease

    International Nuclear Information System (INIS)

    Alazraki, N.; Lawrence, P.F.; Syverud, J.B.

    1984-01-01

    Several non-invasive diagnostic techniques including segmental limb blood pressures, skin fluoresence, and photo plethysmography, have been evaluated as predictors of skin ulcer healing in patients with peripheral vascular disease, but none are widely used. Using 20mCi of Tc-99m phosphate compounds, four phase bone scans were obtained, including (1) radionuclide angiogram (2) blood pool image (3) 2 hour and 4-6 hour static images and (4) 24 hour static delayed images. The first two phases were used to assess vacularity to the region of distal extremity ulceration; the last two phases evaluated presence or absence of osteomyelitis. Studies were performed in 30 patients with non-healing ulcers of the lower extremities. Perfusion to the regions of ulceration on images was graded as normal, increased, or reduced with respect to the opposite (presumed normal) limb or some other normal reference area. Hypervascular response was interpreted as good prognosis for healing unless osteomyelitis was present. Clinicians followed patients for 14 days to assess limb healing with optimum care. If there was no improvement, angiography and/or surgery (reconstructive surgery, sympathectomy, or amputation) was done. Results showed: sensitivity for predicting ulcer healing was 94%, specificity 89%. Patients who failed to heal their ulcers showed reduced perfusion, no hypervascular response, or osteomyelitis. Microcirculatory adequacy for ulcer healing appear predictable by this technique

  17. Evaluation of left ventricular function during exercise in patients with ischemic heart disease using multigated blood pool scintigraphy

    International Nuclear Information System (INIS)

    Ohmori, Yoshiaki; Kanoh, Yasushi; Shiotani, Hideyuki; Fujitani, Kazuhiro; Fukuzaki, Hisashi; Kajiya, Teishi; Nakashima, Yoshiharu; Maeda, Kazumi.

    1985-01-01

    Multigated blood pool scintigraphy (exercise RI ventriculography) and exercise stress thallium-201 myocardial scintigraphy were performed in 44 ischemic heart disease (IHD) patients (16 with angina pectoris and 28 with old myocardial infarction) and 11 healthy persons. Furthermore, blood circulation was examined in 38 of the subjects. Work load was significantly greater, and the number of diseased vessels and the incidence of indicators for transient ischemia during exercise were significantly lower in the group with a remarkably increased left ventricular ejection fraction (EF) during exercise than in the group with a remarkably decreased EF. In the group with unchanged EF, reginal left ventricular wall movement could be assessed using phase analysis. In IHD patients with a remarkably decreased EF at rest, EF was scarcely changed during exercise, and indicators for transient ischemia were not observed frequently. There was a highly significnat correlation between EF during exercise and pulmonary artery wedge pressure or cardiac index during exercise, suggesting that EF is a noninvasive indicator for coronary circulation during exercise. Exercise RI ventriculography was considered useful for evaluating the physiology of IHD. (Namekawa, K.)

  18. Absolute quantification of regional renal blood flow in swine by dynamic contrast-enhanced magnetic resonance imaging using a blood pool contrast agent.

    Science.gov (United States)

    Lüdemann, Lutz; Nafz, Benno; Elsner, Franz; Grosse-Siestrup, Christian; Meissler, Michael; Kaufels, Nicola; Rehbein, Hagen; Persson, Pontus B; Michaely, Henrik J; Lengsfeld, Philipp; Voth, Matthias; Gutberlet, Matthias

    2009-03-01

    To evaluate for the first time in an animal model the possibility of absolute regional quantification of renal medullary and cortical perfusion by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using a blood pool contrast agent. A total of 18 adult female pigs (age, 16-22 weeks; body weight, 45-65 kg; no dietary restrictions) were investigated by DCE-MRI. Absolute renal blood flow (RBF) measured by an ultrasound transit time flow probe around the renal vein was used as the standard of reference. An inflatable stainless cuff placed around the renal artery near its origin from the abdominal aorta was used to reduce RBF to 60%, 40%, and 20% of the baseline flow. The last measurement was performed with the cuff fully reopened. Absolute RBF values during these 4 perfusion states were compared with the results of DCE-MRI performed on a 1.5-T scanner with an 8-channel phased-array surface coil. All scans were acquired in breath-hold technique in the coronal plane using a field of view of 460 mm.Each dynamic scan commenced with a set of five 3D T1-weighted gradient echo sequences with different flip angles (alpha = 2 degrees, 5 degrees, 10 degrees, 20 degrees, 30 degrees): TE, 0.88 milliseconds; TR, 2.65 milliseconds; slice thickness, 8.8 mm for 4 slices; acquisition matrix, 128 x 128; and acquisitions, 4. These data served to calculate 3D intrinsic longitudinal relaxation rate maps (R10) and magnetization (M0). Immediately after these images, the dynamic 3D T1-weighted gradient echo images were acquired with the same parameters and a constant alpha = 30 degrees, half Fourier, 1 acquisition, 64 frames, a time interval of 1.65 seconds between each frame, and a total duration of 105.6. Three milliliters of an albumin-binding blood pool contrast agent (0.25 mmol/mL gadofosveset trisodium, Vasovist, Bayer Schering Pharma AG, Berlin, Germany) was injected at a rate of 3 mL/s. Perfusion was calculated using the arterial input function from the aorta, which was

  19. Assessment of left ventricular function by gated cardiac blood-pool emission computed tomography using a rotating gamma camera

    International Nuclear Information System (INIS)

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa; Honda, Minoru

    1991-01-01

    To elucidate the usefulness of gated cardiac blood-pool single photon emission CT (SPECT) with Tc-99m for the evaluation of left ventricular (LV) global and regional functions, 18 patients with coronary artery disease were studied. Thirty-two gated projection images were obtained over 360-degree at 16 frames per cardiac cycle. As LV volume was calculated by integrating the numbers of voxels which constituted LV and multiplying by the volume of a single voxel (0.1143 ml), we performed phantom studies to determine the appropriate cut-off level to detect LV outline. These cut-off levels were affected by the background activity and organ volume itself. So we constructed Volume-Cut-Level-Curve at each background activity. In clinical studies, short axis images which constituted LV were selected and provisional LV volumes were calculated at the cut-off levels of 45, 50 and 55%. These volumes were plotted on the Volume-Cut-Level-Curve and the true cut-off levels were obtained to calculate LV end-diastolic or end-systolic volume (EDV, ESV). The cut-off levels were different at every patient and ED or ES. EDV, ESV and LV ejection fraction obtained by SPECT were correlatd well with those obtained by contrast ventriculography (LVG) (r=0.89, 0.94, 0.94 each, p<0.01). For the LV wall motion analysis, LVGs obtained at two projections were compared with SPECT or gated cardiac blood-pool planar imaging (Planar) in 5 segments. In addition to visual comparison, wall motion scores (WMS) based on the degree of wall motion abnormality were calculated in each segment. Correlation of WMS between LVG and SPECT (r=0.84) was significantly (p<0.01) superior to that between LVG and Planar (r=0.62). Especially in SPECT, wall motion analyses at septal and infero-posterior segments were superior to those in Planar. Although gated SPECT requires relatively long time to perform, it is a useful method to detect LV global and regional functions. (author)

  20. Gd-DTPA L-cystine bisamide copolymers as novel biodegradable macromolecular contrast agents for MR blood pool imaging.

    Science.gov (United States)

    Kaneshiro, Todd L; Ke, Tianyi; Jeong, Eun-Kee; Parker, Dennis L; Lu, Zheng-Rong

    2006-06-01

    The purpose of this study was to synthesize biodegradable Gd-DTPA L-cystine bisamide copolymers (GCAC) as safe and effective, macromolecular contrast agents for magnetic resonance imaging (MRI) and to evaluate their biodegradability and efficacy in MR blood pool imaging in an animal model. Three new biodegradable GCAC with different substituents at the cystine bisamide [R = H (GCAC), CH2CH2CH3 (Gd-DTPA L-cystine bispropyl amide copolymers, GCPC), and CH(CH3)2 (Gd-DTPA cystine bisisopropyl copolymers, GCIC)] were prepared by the condensation copolymerization of diethylenetriamine pentaacetic acid (DTPA) dianhydride with cystine bisamide or bisalkyl amides, followed by complexation with gadolinium triacetate. The degradability of the agents was studied in vitro by incubation in 15 microM cysteine and in vivo with Sprague-Dawley rats. The kinetics of in vivo contrast enhancement was investigated in Sprague-Dawley rats on a Siemens Trio 3 T scanner. The apparent molecular weight of the polydisulfide Gd(III) chelates ranged from 22 to 25 kDa. The longitudinal (T1) relaxivities of GCAC, GCPC, and GCIC were 4.37, 5.28, and 5.56 mM(-1) s(-1) at 3 T, respectively. The polymeric ligands and polymeric Gd(III) chelates readily degraded into smaller molecules in incubation with 15 microM cysteine via disulfide-thiol exchange reactions. The in vitro degradation rates of both the polymeric ligands and macromolecular Gd(III) chelates decreased as the steric effect around the disulfide bonds increased. The agents readily degraded in vivo, and the catabolic degradation products were detected in rat urine samples collected after intravenous injection. The agents showed strong contrast enhancement in the blood pool, major organs, and tissues at a dose of 0.1 mmol Gd/kg. The difference of their in vitro degradability did not significantly alter the kinetics of in vivo contrast enhancement of the agents. These novel GCAC are promising contrast agents for cardiovascular and tumor MRI

  1. Ventricular emptying performance in patients with tetralogy of Fallot; Assessment with Fourier analysis of gated blood-pool data

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kan; Maeda, Hisato; Nakagawa, Tsuyoshi; Ito, Tsunao; Yamaguchi, Nobuo; Matsuda, Akira (Mie Univ., Tsu (Japan). School of Medicine)

    1989-12-01

    Comparison of emptying patterns between left and right ventricles (LV, RV) was performed with Fourier analysis of gated blood-pool data in patients with tetralogy of Fallot (TF). Using global time-activity curves, the phase and amplitude at the first-harmonic component of Fourier series were calculated and emptying patterns of both ventricles were evaluated by phase difference {l brace}D(phase)=RV phase minus LV phase{r brace} and RV/LV amplitude ratio {l brace}R(amp){r brace}. In 20 patients with normal cardiac function, D(phase) was minimal (mean 2.0{plus minus}6.6 degrees) and R(amp) was less than 1.0 (mean 0.60{plus minus}0.19). In 11 patients with TF, D(phase) was significantly larger than normal, with a mean value of 24.3{plus minus}10.0 degrees (p<0.01) and became greater in a reversed proportion to the ratio of the pulmonary-to-systemic blood flow (p<0.01). In all but one cases with TF, R(amp) was greater than 1.0 with a mean value of 1.4{plus minus}0.4, significantly larger than normal (p<0.001). Furthermore, using time-activity curves approximated by terms up to the 3rd-harmonic component, the temporal difference in emptying patterns between both ventricles was investigated. In TF cases, the time from end-diastole to minimum count (T2) was significantly larger in RV than in LV (p<0.001). The elongated T2 interval of RV seemed to play an important role in producing RV phase lag. Thus, this non-invasive method is valuable for pathophysiologic investigation of patients with TF and can be of help in estimating the severity of their disease. (author).

  2. Manufacture of endothelial colony-forming progenitor cells from steady-state peripheral blood leukapheresis using pooled human platelet lysate.

    Science.gov (United States)

    Siegel, Georg; Fleck, Erika; Elser, Stefanie; Hermanutz-Klein, Ursula; Waidmann, Marc; Northoff, Hinnak; Seifried, Erhard; Schäfer, Richard

    2018-05-01

    Endothelial colony-forming progenitor cells (ECFCs) are promising candidates for cell therapies. However, ECFC translation to the clinic requires optimized isolation and manufacture technologies according to good manufacturing practice (GMP). ECFCs were manufactured from steady-state peripheral blood (PB) leukapheresis (11 donors), using GMP-compliant technologies including pooled human platelet (PLT) lysate, and compared to human umbilical cord endothelial cells, human aortic endothelial cells, and human cerebral microvascular endothelial cells. Specific variables assessed were growth kinetics, phenotype, trophic factors production, stimulation of tube formation, and Dil-AcLDL uptake. ECFCs could be isolated from PB leukapheresis units with mean processed volume of 5411 mL and mean white blood cell (WBC) concentration factor of 8.74. The mean frequency was 1.44 × 10 -8 ECFCs per WBC, corresponding to a mean of 177.8 ECFCs per apheresis unit. Expandable for up to 12 cumulative population doublings, calculated projection showed that approximately 730 × 10 3 ECFCs could be manufactured from 1 apheresis unit. ECFCs produced epidermal growth factor, hepatocyte growth factor, vascular endothelial growth factor (VEGF)-A, PLT-derived growth factor-B, interleukin-8, and monocyte chemoattractant protein-1, featured high potential for capillary-like tubes formation, and showed no telomerase activity. They were characterized by CD29, CD31, CD44, CD105, CD117, CD133, CD144, CD146, and VEGF-R2 expression, with the most common subpopulation CD34+CD117-CD133-. Compared to controls, ECFCs featured greater Dil-AcLDL uptake and higher expression of CD29, CD31, CD34, CD44, CD144, and VEGF-R2. Here we show that isolation of ECFCs with proangiogenic profile from steady-state PB leukapheresis is feasible, marking a first step toward ECFC product manufacture according to GMP. © 2018 AABB.

  3. The effect of varying the acquisition angle on processing and ejection fractions in gated blood pool studies

    International Nuclear Information System (INIS)

    Hughes, K.; Schults, C.G.; Trinh, T.

    2002-01-01

    Full text: Suboptimal ventricular definition has been blamed for difficulties in processing and variations in Ejection Fraction (EF). Clinical patients had Gated Blood Pool Studies (GBPS) performed by one of two operators, ensuring good left ventricular separation and definition. With patient consent, another study was acquired with the camera angle altered in the caudal or septal plane. Using GE Entegra GBPS Software, which allows some operator involvement in modifying the automated systolic and diastolic regions, the studies were analysed by eight 'blinded' technologists. Analyses of optimal and suboptimal acquisitions were compared. The mean, standard deviation (SD) and coefficient of variation (CV%) were determined for each patient's set of EFs. There was no significant difference in the means of the optimal and suboptimal groups (61.2% and 61.7%). One third of the suboptimal studies acquired gave a mean EF that differed by more than 5% from the Optimal' mean. The average CV of all analyses was 4.5%. The optima] group CV 4.7% (septal 4.6%/caudal 4.8%) and the suboptimal group CV 4.3% (septal 4.5%/caudal 4.2%). The analysis demonstrates that precision of processing GBPS is not affected when the study is acquired at a suboptimal angle. Although most EF results are reliable when acquired at a suboptimal angle, approximately one third will produce an EF that varies from the optimal result by more than 5%. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  4. Integrating atlas and graph cut methods for right ventricle blood-pool segmentation from cardiac cine MRI

    Science.gov (United States)

    Dangi, Shusil; Linte, Cristian A.

    2017-03-01

    Segmentation of right ventricle from cardiac MRI images can be used to build pre-operative anatomical heart models to precisely identify regions of interest during minimally invasive therapy. Furthermore, many functional parameters of right heart such as right ventricular volume, ejection fraction, myocardial mass and thickness can also be assessed from the segmented images. To obtain an accurate and computationally efficient segmentation of right ventricle from cardiac cine MRI, we propose a segmentation algorithm formulated as an energy minimization problem in a graph. Shape prior obtained by propagating label from an average atlas using affine registration is incorporated into the graph framework to overcome problems in ill-defined image regions. The optimal segmentation corresponding to the labeling with minimum energy configuration of the graph is obtained via graph-cuts and is iteratively refined to produce the final right ventricle blood pool segmentation. We quantitatively compare the segmentation results obtained from our algorithm to the provided gold-standard expert manual segmentation for 16 cine-MRI datasets available through the MICCAI 2012 Cardiac MR Right Ventricle Segmentation Challenge according to several similarity metrics, including Dice coefficient, Jaccard coefficient, Hausdorff distance, and Mean absolute distance error.

  5. SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

    Science.gov (United States)

    Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

    2016-01-01

    Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions.

  6. Gated blood-pool SPECT assessment of Wolff-Parkinson-White syndromes before and after radiofrequency ablation of accessory pathways

    International Nuclear Information System (INIS)

    Bontemps, L.; Ben Brahim, H.; Kraiem, T.; Chevalier, P.; Kirkorian, G.; Touboul, P.; Itti, R.

    1997-01-01

    Radiofrequency (RF) ablation of accessory pathways in Wolff-Parkinson-White (WPW) syndrome is supposed to be less aggressive than fulguration while providing excellent results. The aims of our study were therefore the evaluation of the functional results of this therapy in terms of left or right ejection fractions and its effects on the contraction synchronism between both ventricular chambers, derived from bi-ventricular Fourier phase histograms. A consecutive series of 44 patients has been investigated within 48 hours before and after RF therapy: 14 patients had right sided WPW and 30 patients left sided WPW. Only patients for whom RF treatment was considered as a success have been included in the study. Gated blood pool tomography has been performed in order to localize the site of pre-excitation and to build-up the phase histograms for both ventricles, and planar gated imaging has been used for right and left ejection fraction determination. Functional results demonstrate the absence of deleterious effect of RF on ventricular contraction and rather a slight increase of ejection fractions, with a more statistically significant difference for left WPW (LVEF = 62.2 % before RF vs 64.4 % after RF; p = 0.02) than for right WPW (RVEF = 36.3 % before RF vs 39.7 after RF; p = 0.16). Phase analysis, on the contrary, show only significant differences for right WPW, with a noticeable decrease of the pre-excitation (left-to-right phase difference 14.4 deg before RF vs 7.5 deg after RF; p = 0.03) and a significant reduction of the right ventricular phase dispersion (right phase standard deviation 26.5 deg before RF vs 19.0 deg after RF; p = 0.03). For left WPW no measurable differences can be demonstrated in the basal state and it is suggested to use stimulation techniques in order to enhance the competition between the normal and accessory conduction pathways. (authors)

  7. Comparison of blood pool and extracellular gadolinium chelate for functional MR evaluation of vascular thoracic outlet syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ruth P., E-mail: ruthplim74@gmail.com [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Austin Health, Department of Radiology, Heidelberg, Victoria 3084 (Australia); The University of Melbourne, School of Medicine, Parkville, Victoria 3010 (Australia); Bruno, Mary, E-mail: mary.bruno@nyumc.org [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Rosenkrantz, Andrew B., E-mail: Andrew.rosenkrantz@nyumc.org [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Kim, Danny C., E-mail: danny.kim@nyumc.org [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Mulholland, Thomas, E-mail: Thomas.mulholland@nyumc.org [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Kwon, Jane, E-mail: jane.kwon@nyumc.org [New York University School of Medicine, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, 660 1st Avenue, New York, NY 10016 (United States); Palfrey, Amy P., E-mail: amy.pastva10@stjohns.edu [St John' s University, Department of Psychology, 8000 Utopia Parkway, Jamaica-Queens, NY 11439 (United States); Ogedegbe, Olugbenga, E-mail: Olugbenga.Ogedegbe@nyumc.org [New York University School of Medicine, Clinical and Translational Science Institute, 227 E30th St, 8th Floor, New York, NY 10016 (United States)

    2014-07-15

    Objective: To compare performance of single-injection blood pool agent (gadofosveset trisodium, BPA) against dual-injection extracellular contrast (gadopentetate dimeglumine, ECA) for MRA/MRV in assessment of suspected vascular TOS. Materials and methods: Thirty-one patients referred for vascular TOS evaluation were assessed with BPA (n = 18) or ECA (n = 13) MRA/MRV in arm abduction and adduction. Images were retrospectively assessed for: image quality (1 = non-diagnostic, 5 = excellent), vessel contrast (1 = same signal as muscle, 4 = much brighter than muscle) and vascular pathology by two independent readers, with a separate experienced reader providing reference assessment of vascular pathology. Results: Median image quality was diagnostic or better (score ≥3) for ECA and BPA at all time points, with BPA image quality superior at abduction late (BPA 4.5, ECA 4, p = 0.042) and ECA image quality superior at adduction-early (BPA 4.5; ECA 4.0, p = 0.018). High qualitative vessel contrast (mean score ≥3) was observed at all time points with both BPA and ECA, with superior BPA vessel contrast at abduction-late (BPA 3.97 ± 0.12; ECA 3.73 ± 0.26, p = 0.007) and ECA at adduction-early (BPA 3.42 ± 0.52; ECA 3.96 ± 0.14, p < 0.001). Readers readily identified arterial and venous pathology with BPA, similar to ECA examinations. Conclusion: Single-injection BPA MRA/MRV for TOS evaluation demonstrated diagnostic image quality and high vessel contrast, similar to dual-injection ECA imaging, enabling identification of fixed and functional arterial and venous pathology.

  8. Blood Pool Contrast-enhanced Magnetic Resonance Angiography with Correlation to Digital Subtraction Angiography: A Pictorial Review

    Directory of Open Access Journals (Sweden)

    Martha-Grace Knuttinen

    2014-01-01

    Full Text Available Magnetic resonance angiography (MRA provides noninvasive visualization of the vascular supply of soft tissue masses and vascular pathology, without harmful radiation. This is important for planning an endovascular intervention, and helps to evaluate the efficiency and effectiveness of the treatment. MRA with conventional extracellular contrast agents relies on accurate contrast bolus timing, limiting the imaging window to first-pass arterial phase. The recently introduced blood pool contrast agent (BPCA, gadofosveset trisodium, reversibly binds to human serum albumin, resulting in increased T1 relaxivity and prolonged intravascular retention time, permitting both first-pass and steady-state phase high-resolution imaging. In our practice, high-quality MRA serves as a detailed "roadmap" for the needed endovascular intervention. Cases of aortoiliac occlusive disease, inferior vena cava thrombus, pelvic congestion syndrome, and lower extremity arteriovenous malformation are discussed in this article. MRA was acquired at 1.5 T with an 8-channel phased array coil after intravenous administration of gadofosveset (0.03 mmol/kg body weight, at the first-pass phase. In the steady-state, serial T1-weighted 3D spoiled gradient echo images were obtained with high resolution. All patients underwent digital subtraction angiography (DSA and endovascular treatment. MRA and DSA findings of vascular anatomy and pathology are discussed and correlated. BPCA-enhanced MRA provides high-quality first-pass and steady-state vascular imaging. This could increase the diagnostic accuracy and create a detailed map for pre-intervention planning. Understanding the pharmacokinetics of BPCA and being familiar with the indications and technique of MRA are important for diagnosis and endovascular intervention.

  9. The problem in 180 deg data sampling and radioactivity decay correction in gated cardiac blood pool scanning using SPECT

    International Nuclear Information System (INIS)

    Ohtake, Tohru; Watanabe, Toshiaki; Nishikawa, Junichi

    1986-01-01

    In cardiac blood pool scanning using SPECT, half 180 deg data collection (HD) vs. full 360 deg data collection (FD) and Tc-99m decay are problems in quantifying the ejection count (EC) (end-diastolic count - end-systolic count) of both ventricles and the ratio of the ejection count of the right and left ventricles (RVEC/LVEC). We studied the change produced by altering the starting position of data sampling in HD scans. In our results of phantom and 4 clinical cases, when the cardiac axis deviation was not large and there was not remarkable cardiac enlargement, the change in LVEC, RVEC and RVEC/LVEC was small (1 - 4 %) within 12 degree change of the starting position, and the difference between the results of HD scan with a good starting position (the average of LV peak and RV peak) and FD scan was not large (less than 7 %). Because of this, we think HD scan can be used in those cases. But when the cardiac axis deviation was large or there was remarkable cardiac enlargement, the change of LVEC, RVEC and RVEC/LVEC was large (more than 10 %) even within 12 degree change of the starting position. So we think FD scan would be better in those cases. In our results of 6 patients, the half-life of Tc-99m labeled albumin in blood varied from 2 to 4 hr (3.03 ± 0.59 hr, mean ± s.d.). Using a program for radioactivity (RA) decay correction, we studied the change in LVEC, RVEC and LVEC/RVEC in 11 cases. When RA decay correction was performed using a halflife of 3.0 hr, LVEC increased 7.5 %, RVEC increased 8.7 % and RVEC/LVEC increased 0.9 % on the average in HD scans of 8 cases (LPO to RAO, 32 views, 60 beat/1 view). We think RA decay correction would not be needed in quantifying RVEC/LVEC in most cases because the change of RVEC/LVEC was very small. (author)

  10. Rapid MR venography in children using a blood pool contrast agent and multi-station fat-water-separated volumetric imaging

    International Nuclear Information System (INIS)

    Ghanouni, Pejman; Walters, Shannon G.; Vasanawala, Shreyas S.

    2012-01-01

    A rapid, reliable radiation-free method of pediatric body venography might complement US by evaluating veins in the abdomen and pelvis and by providing a global depiction of venous anatomy. We describe a MR venography technique utilizing gadofosveset, a blood pool contrast agent, in children. The technique allows high-spatial-resolution imaging of the veins from the diaphragm to the knees in less than 15 min of total exam time. (orig.)

  11. High spatial resolution and high contrast visualization of brain arteries and veins. Impact of blood pool contrast agent and water-selective excitation imaging at 3T

    International Nuclear Information System (INIS)

    Spuentrup, E.; Jacobs, J.E.; Kleimann, J.F.

    2010-01-01

    Purpose: To investigate a blood pool contrast agent and water-selective excitation imaging at 3 T for high spatial and high contrast imaging of brain vessels including the veins. Methods and Results: 48 clinical patients (47 ± 18 years old) were included. Based on clinical findings, twenty-four patients received a single dose of standard extracellular Gadoterate-meglumine (Dotarem registered ) and 24 received the blood pool contrast agent Gadofosveset (Vasovist registered ). After finishing routine MR protocols, all patients were investigated with two high spatial resolution (0.15 mm 3 voxel size) gradient echo sequences in random order in the equilibrium phase (steady-state) as approved by the review board: A standard RF-spoiled gradient-echo sequence (HR-SS, TR/TE 5.1 / 2.3 msec, FA 30 ) and a fat-suppressed gradient-echo sequence with water-selective excitation (HR-FS, 1331 binominal-pulse, TR/TE 8.8 / 3.8 msec, FA 30 ). The images were subjectively assessed (image quality with vessel contrast, artifacts, depiction of lesions) by two investigators and contrast-to-noise ratios (CNR) were compared using the Student's t-test. The image quality and CNR in the HR-FS were significantly superior compared to the HR-SS for both contrast agents (p < 0.05). The CNR was also improved when using the blood pool agent but only to a minor extent while the subjective image quality was similar for both contrast agents. Conclusion: The utilized sequence with water-selective excitation improved image quality and CNR properties in high spatial resolution imaging of brain arteries and veins. The used blood pool contrast agent improved the CNR only to a minor extent over the extracellular contrast agent. (orig.)

  12. Cardiac cine MRI: Comparison of 1.5 T, non-enhanced 3.0 T and blood pool enhanced 3.0 T imaging

    International Nuclear Information System (INIS)

    Gerretsen, S.C.; Versluis, B.; Bekkers, S.C.A.M.; Leiner, T.

    2008-01-01

    Introduction: Cardiac cine imaging using balanced steady state free precession sequences (bSSFP) suffers from artefacts at 3.0 T. We compared bSSFP cardiac cine imaging at 1.5 T with gradient echo imaging at 3.0 T with and without a blood pool contrast agent. Materials and methods: Eleven patients referred for cardiac cine imaging underwent imaging at 1.5 T and 3.0 T. At 3.0 T images were acquired before and after administration of 0.03 mmol/kg gadofosveset. Blood pool signal-to-noise ratio (SNR), temporal variations in SNR, ejection fraction and myocardial mass were compared. Subjective image quality was scored on a four-point scale. Results: Blood pool SNR increased with more than 75% at 3.0 T compared to 1.5 T (p < 0.001); after contrast administration at 3.0 T SNR increased with 139% (p < 0.001). However, variations in blood pool SNR at 3.0 T were nearly three times as high versus those at 1.5 T in the absence of contrast medium (p < 0.001); after contrast administration this was reduced to approximately a factor 1.4 (p = 0.21). Saturation artefacts led to significant overestimation of ejection fraction in the absence of contrast administration (1.5 T: 44.7 ± 3.1 vs. 3.0 T: 50.7 ± 4.2 [p = 0.04] vs. 3.0 T post contrast: 43.4 ± 2.9 [p = 0.55]). Subjective image quality was highest for 1.5 T (2.8 ± 0.3), and lowest for non-enhanced 3.0 T (1.7 ± 0.6; p = 0.006). Conclusions: GRE cardiac cine imaging at 3.0 T after injection of the blood pool agent gadofosveset leads to improved objective and subjective cardiac cine image quality at 3.0 T and to the same conclusions regarding cardiac ejection fraction compared to bSSFP imaging at 1.5 T

  13. Worldwide trends in blood pressure from 1975 to 2015: a pooled analysis of 1479 population-based measurement studies with 19·1 million participants.

    Science.gov (United States)

    2017-01-07

    Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood pressure of 140 mm Hg or higher or diastolic blood pressure of 90 mm Hg or higher. For this analysis, we pooled national, subnational, or community population-based studies that had measured blood pressure in adults aged 18 years and older. We used a Bayesian hierarchical model to estimate trends from 1975 to 2015 in mean systolic and mean diastolic blood pressure, and the prevalence of raised blood pressure for 200 countries. We calculated the contributions of changes in prevalence versus population growth and ageing to the increase in the number of adults with raised blood pressure. We pooled 1479 studies that had measured the blood pressures of 19·1 million adults. Global age-standardised mean systolic blood pressure in 2015 was 127·0 mm Hg (95% credible interval 125·7-128·3) in men and 122·3 mm Hg (121·0-123·6) in women; age-standardised mean diastolic blood pressure was 78·7 mm Hg (77·9-79·5) for men and 76·7 mm Hg (75·9-77·6) for women. Global age-standardised prevalence of raised blood pressure was 24·1% (21·4-27·1) in men and 20·1% (17·8-22·5) in women in 2015. Mean systolic and mean diastolic blood pressure decreased substantially from 1975 to 2015 in high-income western and Asia Pacific countries, moving these countries from having some of the highest worldwide blood pressure in 1975 to the lowest in 2015. Mean blood pressure also decreased in women in central and eastern Europe, Latin America and the Caribbean, and, more recently, central Asia, Middle East, and north Africa, but the estimated trends in these super-regions had larger uncertainty than in high-income super-regions. By contrast, mean blood pressure might have increased in east and southeast

  14. Assessment of left ventricular function by gated myocardial perfusion and gated blood-pool SPECT. Can we use the same reference database?

    Energy Technology Data Exchange (ETDEWEB)

    Paul, A.K.; Hasegawa, Shinji; Yoshioka, Jun; Yamaguchi, Hitoshi; Tsujimura, Eiichiro; Nishimura, Tsunehiko [Osaka Univ., Suita (Japan). Graduate School of Medicine

    2000-04-01

    The purpose of this study was to compare left ventricular (LV) volume and ejection fraction (LVEF) measurements obtained with electrocardiographic gated single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (GS-MPI) with those obtained with gated SPECT cardiac blood-pool imaging (GS-pool). Fifteen patients underwent GS-MPI with technetium-99m tetrofosmin and GS-pool with technetium-99m-erythrocyte, within a mean interval of 8{+-}3 days. Eight patients had suspected dilated cardiomyopathy and seven patients had angiographically significant coronary artery disease. End-diastolic volume (EDV), end-systolic volume (ESV) and LVEF measurements were estimated from GS-MPI images by means of Cedars-Sinai automatic quantitative program and from GS-pool images by the threshold technique. Mean differences between GS-MPI and GS-pool in EDV, ESV and LVEF measurements were -2.8{+-}10.5 ml [95% confidence interval (CI): -8.6{+-}3.0 ml], 2.6{+-}7.3 ml (CI: -1.4-6.6 ml) and -2.3{+-}5.1% (CI: -5.1-0.6%), respectively. No significant difference in the mean differences from 0 was found for EDV, ESV or LVEF measurements. Bland-Altman plots revealed no trend over the measured LV volumes and LVEF. For all parameters, regression lines approximated lines of identity. The excellent agreement between GS-MPI and GS-pool measurements suggests that, for estimation of LV volumes and LVEF, these two techniques may be used interchangeably and measurements by one method can serve as a reference for the other. (author)

  15. Temporally resolved electrocardiogram-triggered diffusion-weighted imaging of the human kidney: correlation between intravoxel incoherent motion parameters and renal blood flow at different time points of the cardiac cycle.

    Science.gov (United States)

    Wittsack, Hans-Jörg; Lanzman, Rotem S; Quentin, Michael; Kuhlemann, Julia; Klasen, Janina; Pentang, Gael; Riegger, Caroline; Antoch, Gerald; Blondin, Dirk

    2012-04-01

    To evaluate the influence of pulsatile blood flow on apparent diffusion coefficients (ADC) and the fraction of pseudodiffusion (F(P)) in the human kidney. The kidneys of 6 healthy volunteers were examined by a 3-T magnetic resonance scanner. Electrocardiogram (ECG)-gated and respiratory-triggered diffusion-weighted imaging (DWI) and phase-contrast flow measurements were performed. Flow imaging of renal arteries was carried out to quantify the dependence of renal blood flow on the cardiac cycle. ECG-triggered DWI was acquired in the coronal plane with 16 b values in the range of 0 s/mm(2) and 750 s/mm(2) at the time of minimum (MIN) (20 milliseconds after R wave) and maximum renal blood flow (MAX) (197 ± 24 milliseconds after R wave). The diffusion coefficients were calculated using the monoexponential approach as well as the biexponential intravoxel incoherent motion model and correlated to phase-contrast flow measurements. Flow imaging showed pulsatile renal blood flow depending on the cardiac cycle. The mean flow velocity at MIN was 45 cm/s as compared with 61 cm/s at MAX. F(p) at MIN (0.29) was significantly lower than at MAX (0.40) (P = 0.001). Similarly, ADC(mono), derived from the monoexponential model, also showed a significant difference (P renal blood flow and F(p) (r = 0.85) as well as ADC(mono) (r = 0.67) was statistically significant. Temporally resolved ECG-gated DWI enables for the determination of the diffusion coefficients at different time points of the cardiac cycle. ADC(mono) and FP vary significantly among acquisitions at minimum (diastole) and maximum (systole) renal blood flow. Temporally resolved ECG-gated DWI might therefore serve as a novel technique for the assessment of pulsatility in the human kidney.

  16. Clinical application of a right ventricular pressure-volume loop determined by gated blood-pool imaging and simultaneously measured right ventricular pressure

    International Nuclear Information System (INIS)

    Yasue, Takao; Watanabe, Sachiro; Sugishita, Nobuyoshi; Tanaka, Tsutomu; Yokoyama, Hideo

    1983-01-01

    The data obtained by ECG-gated radionuclide angiography were collected simultaneously with right ventricular pressure and thermal cardiac output (CO) obtained by a Swan-Ganz catheter in Scintipac 1200 (Shimazu Co) in order to create a right ventricular pressure-volume (RV P-V) loop. Subjects consisted of 15 patients with old myocardial infarction (MI group), seven with angina pectoris (AP group), six with congestive cardiomyopathy (CCM group) and five with neurocirculatory asthenia (NCA group). Right ventricular end-diastolic volume (RVEDV) was calculated as RVEDV = CO/(EF x HR) (CO = cardiac output; HR = heart rate). Systolic work (W sub(S)), diastolic work (W sub(D)) and net work (W sub(N)) were calculated from a RV P-V loop by Simpson's method. The measurements were performed before and 5 min after sublingual administration of nitroglycerin (NG) (0.3 mg). The results were as follows: 1. RV P-V loops shifted towards the left lower part of the P-V plane after sublingual administration of nitroglycerin, indicating the reduction of pressure and volume of the right ventricle. 2. Right ventricular ejection fraction (RVEF) in the MI, AP and CCM groups showed smaller values than that of the NCA group. 3. Right ventricular end-diastolic volume index (RVEDVI) showed a converse relation with RVEF. 4. Cardiac index in all groups decreased after NG and a statistical significance was seen in the MI, AP and NCA groups (p<0.05). 5. RV W sub(S), RV W sub(D) and RV W sub(N) showed no difference among each groups in the control state, and significantly decreased after NG. We conclude that the present method using RV P-V loop might be useful as a noninvasive bedside monitoring and permits the evaluation of RV function in a clinical setting

  17. Proposta do uso de pool de sangue total como controle interno de qualidade em hematologia Proposal for the use of a pool of whole blood as internal quality control in hematology

    Directory of Open Access Journals (Sweden)

    Carina Daniele Schons

    2010-06-01

    Full Text Available INTRODUÇÃO: A confiabilidade dos resultados do laboratório é garantida pela realização do controle de qualidade, que tem como funções básicas análise, pesquisa e prevenção da ocorrência de erros laboratoriais por meio de programas que abrangem tanto o controle interno quanto o externo. OBJETIVO: Propor a padronização de utilização de pool de sangue total como controle interno de qualidade no setor de hematologia. MÉTODO: Foram selecionadas amostras de sangue total, colhidas com ácido etilenodiaminotetracético (EDTA, de mesmos grupo sanguíneo e fator Rh, livres de interferentes, como hemólise, lipemia e icterícia. De um total de 30 ml de sangue total, obtiveram-se três alíquotas de 10 ml cada, às quais foram adicionados, respectivamente, 0 ml (sem adição, 1 ml e 5 ml de glicerol (conservante. As amostras foram avaliadas em contador automático ADVIA® 60. Após determinação dos valores de média e DP, todas as amostras foram avaliadas por um período de 45 dias úteis para confecção do gráfico de Levey-Jennings e verificação da estabilidade da amostra. RESULTADO E CONCLUSÃO: Podemos verificar que o pool de sangue total, preparado de acordo com a metodologia proposta, não apresenta estabilidade necessária para sua utilização, como controle interno alternativo no setor de hematologia.INTRODUCTION: The reliability of laboratory results is ensured by the implementation of quality control, which has basic functions, such as analysis, research and prevention of laboratory errors through programs that encompass both internal and external control. OBJECTIVE: To propose a standard method to use pooled whole blood as internal quality control in the Hematology division. METHOD: The selected whole blood samples were collected with EDTA, belonged to the same blood group and Rh factor and did not present interfering factors, such as hemolysis, lipemia and icterus. From a total of 30 ml of whole blood it was obtained 3

  18. Red blood cells free α-haemoglobin pool: a biomarker to monitor the β-thalassemia intermedia variability. The ALPHAPOOL study.

    Science.gov (United States)

    Vasseur, Corinne; Domingues-Hamdi, Elisa; Ledudal, Katia; Le Corvoisier, Philippe; Barau, Caroline; Ghaleh, Bijan; Rialland, Amandine; Pissard, Serge; Galactéros, Frédéric; Baudin-Creuza, Véronique

    2017-10-01

    The severity of β-thalassaemia (β-thal) intermedia is mainly correlated to the degree of imbalanced α/non α-globin chain synthesis. The phenotypic diversity of β-thal depends on this imbalance and reflects all possible combinations of α- and β-globin genotypes, levels of fetal haemoglobin (HbF) and co-inheritance of other modulating factors. This study aimed to demonstrate the validity of a new surrogate of α/non α-globin biosynthetic ratio by measuring the soluble α-Hb pool in lysed red blood cells. Our results confirm that the α-Hb pool measurement allows a good discrimination between β-thal intermedia patients, controls and α-thal patients (P intermedia patients and may be clinically useful for monitoring the evolution of the disequilibrium of globin synthesis in response to treatments. © 2017 John Wiley & Sons Ltd.

  19. Pre-clinical evaluation of a nanoparticle-based blood-pool contrast agent for MR imaging of the placenta.

    Science.gov (United States)

    Ghaghada, Ketan B; Starosolski, Zbigniew A; Bhayana, Saakshi; Stupin, Igor; Patel, Chandreshkumar V; Bhavane, Rohan C; Gao, Haijun; Bednov, Andrey; Yallampalli, Chandrasekhar; Belfort, Michael; George, Verghese; Annapragada, Ananth V

    2017-09-01

    Non-invasive 3D imaging that enables clear visualization of placental margins is of interest in the accurate diagnosis of placental pathologies. This study investigated if contrast-enhanced MRI performed using a liposomal gadolinium blood-pool contrast agent (liposomal-Gd) enables clear visualization of the placental margins and the placental-myometrial interface (retroplacental space). Non-contrast MRI and contrast-enhanced MRI using a clinically approved conventional contrast agent were used as comparators. Studies were performed in pregnant rats under an approved protocol. MRI was performed at 1T using a permanent magnet small animal scanner. Pre-contrast and post-liposomal-Gd contrast images were acquired using T1-weighted and T2-weighted sequences. Dynamic Contrast enhanced MRI (DCE-MRI) was performed using gadoterate meglumine (Gd-DOTA, Dotarem ® ). Visualization of the retroplacental clear space, a marker of normal placentation, was judged by a trained radiologist. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated for both single and averaged acquisitions. Images were reviewed by a radiologist and scored for the visualization of placental features. Contrast-enhanced CT (CE-CT) imaging using a liposomal CT agent was performed for confirmation of the MR findings. Transplacental transport of liposomal-Gd was evaluated by post-mortem elemental analysis of tissues. Ex-vivo studies in perfused human placentae from normal, GDM, and IUGR pregnancies evaluated the transport of liposomal agent across the human placental barrier. Post-contrast T1w images acquired with liposomal-Gd demonstrated significantly higher SNR (p = 0.0002) in the placenta compared to pre-contrast images (28.0 ± 4.7 vs. 6.9 ± 1.8). No significant differences (p = 0.39) were noted between SNR in pre-contrast and post-contrast liposomal-Gd images of the amniotic fluid, indicating absence of transplacental passage of the agent. The placental margins were

  20. High-throughput strategy for molecular identification of Vel- blood donors employing nucleic acids extracted from plasma pools used for viral nucleic acid test screening.

    Science.gov (United States)

    Dezan, Marcia R; Dinardo, Carla L; Bosi, Silvia R A; Vega, Sileni; Salles, Nanci A; Mendrone-Júnior, Alfredo; Levi, José E

    2016-06-01

    Serologic methods to determine the Vel- phenotype require the use of rare human antisera and do not allow for many samples to be tested simultaneously, which limits their application as a tool to search for rare donors. This study developed a low-cost molecular screening strategy using real-time polymerase chain reaction (PCR) and DNA, extracted from plasma pools for viral nucleic acid test (NAT) screening, to identify Vel- and Vel+(W) donors. A total of 4680 blood donors from the Brazilian southeast region were genotyped through real-time PCR targeting the 17-nucleotide (c.64_80del) deletion in the SMIM1 gene, which determines the Vel- phenotype, by using remaining nucleic acid from plasma pools of six donors, routinely discarded after the release of viral NAT results. Twenty pools tested reactive and individual testing of samples from reactive pools identified 19 heterozygous donors with the SMIM1*64_80del deletion (0.40%) and one homozygous donor (0.02%). Fourteen of the 19 donors were confirmed as Vel- or Vel+(W) using anti-Vel human antiserum. The DNA pool genotyping strategy using real-time PCR designed to detect the deletion in the SMIM1 gene proved effective and accurate in identifying donors with the Vel- and Vel+(W) phenotypes. The fact that remaining nucleic acid from routine viral NAT screening was used makes this technique economically attractive and definitely superior to the serologic techniques available to search for this rare phenotype. © 2016 AABB.

  1. Cash pooling

    OpenAIRE

    Lozovaya, Karina

    2009-01-01

    This work makes a mention of cash management. At next chapter describes two most known theoretical models of cash management -- Baumol Model and Miller-Orr Model. Principal part of work is about cash pooling, types of cash pooling, cash pooling at Czech Republic and influence of cash pooling over accounting and taxes.

  2. Magnetic Particle / Magnetic Resonance Imaging: In-Vitro MPI-Guided Real Time Catheter Tracking and 4D Angioplasty Using a Road Map and Blood Pool Tracer Approach.

    Directory of Open Access Journals (Sweden)

    Johannes Salamon

    Full Text Available In-vitro evaluation of the feasibility of 4D real time tracking of endovascular devices and stenosis treatment with a magnetic particle imaging (MPI / magnetic resonance imaging (MRI road map approach and an MPI-guided approach using a blood pool tracer.A guide wire and angioplasty-catheter were labeled with a thin layer of magnetic lacquer. For real time MPI a custom made software framework was developed. A stenotic vessel phantom filled with saline or superparamagnetic iron oxide nanoparticles (MM4 was equipped with bimodal fiducial markers for co-registration in preclinical 7T MRI and MPI. In-vitro angioplasty was performed inflating the balloon with saline or MM4. MPI data were acquired using a field of view of 37.3×37.3×18.6 mm3 and a frame rate of 46 volumes/sec. Analysis of the magnetic lacquer-marks on the devices were performed with electron microscopy, atomic absorption spectrometry and micro-computed tomography.Magnetic marks allowed for MPI/MRI guidance of interventional devices. Bimodal fiducial markers enable MPI/MRI image fusion for MRI based roadmapping. MRI roadmapping and the blood pool tracer approach facilitate MPI real time monitoring of in-vitro angioplasty. Successful angioplasty was verified with MPI and MRI. Magnetic marks consist of micrometer sized ferromagnetic plates mainly composed of iron and iron oxide.4D real time MP imaging, tracking and guiding of endovascular instruments and in-vitro angioplasty is feasible. In addition to an approach that requires a blood pool tracer, MRI based roadmapping might emerge as a promising tool for radiation free 4D MPI-guided interventions.

  3. Magnetic Particle / Magnetic Resonance Imaging: In-Vitro MPI-Guided Real Time Catheter Tracking and 4D Angioplasty Using a Road Map and Blood Pool Tracer Approach.

    Science.gov (United States)

    Salamon, Johannes; Hofmann, Martin; Jung, Caroline; Kaul, Michael Gerhard; Werner, Franziska; Them, Kolja; Reimer, Rudolph; Nielsen, Peter; Vom Scheidt, Annika; Adam, Gerhard; Knopp, Tobias; Ittrich, Harald

    2016-01-01

    In-vitro evaluation of the feasibility of 4D real time tracking of endovascular devices and stenosis treatment with a magnetic particle imaging (MPI) / magnetic resonance imaging (MRI) road map approach and an MPI-guided approach using a blood pool tracer. A guide wire and angioplasty-catheter were labeled with a thin layer of magnetic lacquer. For real time MPI a custom made software framework was developed. A stenotic vessel phantom filled with saline or superparamagnetic iron oxide nanoparticles (MM4) was equipped with bimodal fiducial markers for co-registration in preclinical 7T MRI and MPI. In-vitro angioplasty was performed inflating the balloon with saline or MM4. MPI data were acquired using a field of view of 37.3×37.3×18.6 mm3 and a frame rate of 46 volumes/sec. Analysis of the magnetic lacquer-marks on the devices were performed with electron microscopy, atomic absorption spectrometry and micro-computed tomography. Magnetic marks allowed for MPI/MRI guidance of interventional devices. Bimodal fiducial markers enable MPI/MRI image fusion for MRI based roadmapping. MRI roadmapping and the blood pool tracer approach facilitate MPI real time monitoring of in-vitro angioplasty. Successful angioplasty was verified with MPI and MRI. Magnetic marks consist of micrometer sized ferromagnetic plates mainly composed of iron and iron oxide. 4D real time MP imaging, tracking and guiding of endovascular instruments and in-vitro angioplasty is feasible. In addition to an approach that requires a blood pool tracer, MRI based roadmapping might emerge as a promising tool for radiation free 4D MPI-guided interventions.

  4. Prediction of cardiac sympathetic nerve activity and cardiac functional outcome after treatment in patients with dilated cardiomyopathy. Examination using dobutamine gated blood pool scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Kasama, Shu; Toyama, Takuji; Iwasaki, Tsutomu; Suzuki, Tadashi [Gunma Univ., Maebashi (Japan). School of Medicine; Hoshizaki, Hiroshi; Oshima, Shigeru; Taniguchi, Koichi; Nagai, Ryozo

    2000-07-01

    This study evaluated whether dobutamine gated blood pool scintigraphy can predict improvement of cardiac sympathetic nerve activity and cardiac function. Sixteen patients (10 men and 6 women, mean age 59{+-}13 years) with dilated cardiomyopathy underwent dobutamine gated blood pool scintigraphy to measure left ventricular ejection fraction (LVEF) using tracer at 0, 5, 10 and 15 {mu}g/kg/min before treatment. Patients were divided into good responders (LVEF increase {>=}15%) 8 patients (GR Group) and poor responders (LVEF increase <15%) 8 patients (PR Group) after treatment with {beta}-blocker or amiodarone with a background treatment of digitalis, diuretics and angiotensin converting enzyme inhibitor. I-123 metaiodobenzylguanidine (MIBG) imaging to evaluate cardiac sympathetic nerve activity and echocardiography were performed before and at one year after treatment. MIBG imaging was obtained 4 hours after tracer injection, and the heart/mediastinum count ratio (H/M ratio) calculated from the anterior planar image and the total defect score (TDS) from the single photon emission computed tomography image. LVEF and left ventricular endo-diastolic dimension (LVDd) were measured by echocardiography and New York Heart Association (NYHA) functional class was evaluated. The GR Group showed TDS decreased from 28{+-}6 to 17{+-}12 (p<0.05), H/M ratio increased from 1.79{+-}0.26 to 2.07{+-}0.32 (p<0.05), LVEF increased from 29{+-}8% to 48{+-}10% (p<0.01), and LVDd decreased from 65{+-}4 mm to 58{+-}5 mm (p<0.05). In contrast, the PR group showed no significant changes in TDS. H/M ratio, LVEF and LVDd. NYHA functional class improved in both groups. The improvement was better in the GR Group than in the PR group. Dobutamine gated blood pool scintigraphy is useful to predict the improvement of the cardiac sympathetic nerve activity and cardiac function, and symptoms after treatment in patients with dilated cardiomyopathy. (author)

  5. Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: a pooled analysis of 1018 population-based measurement studies with 88.6 million participants.

    Science.gov (United States)

    2018-03-19

    Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probit-transformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the high-income Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Change in mean blood pressure is the main driver of the worldwide change in

  6. Visualization of hypertrophied papillary muscle mimicking left ventricular mass on gated blood pool and T1-201 myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Bunko, H.; Nakajima, K.; Tonami, N.; Asanoi, H.; Hisada, K.

    1981-01-01

    A sixty-year old man with acute myocardial infarction was incidentally found to have a hypertrophied anterolateral papillary muscle (ALPPM) of the left ventricle on gated blood pool (GBP) and T1-201 myocardial perfusion images. Hypertrophy of the ALPPM was visualized as a movable defect in the lateral basal area on GBP imaging throughout the cardiac cycle and on the TI-201 study as a radionuclide accumulating structure, consistent with the defect in the GBP. A combination of these findings may suggest the presence of a hypertrophied papillary muscle of the left ventricle

  7. Rapid Blood Pressure Lowering According to Recovery at Different Time Intervals after Acute Intracerebral Hemorrhage: Pooled Analysis of the INTERACT Studies.

    Science.gov (United States)

    Wang, Xia; Arima, Hisatomi; Al-Shahi Salman, Rustam; Woodward, Mark; Heeley, Emma; Stapf, Christian; Lavados, Pablo M; Robinson, Thompson; Huang, Yining; Wang, Jiguang; Delcourt, Candice; Anderson, Craig S

    2015-01-01

    Early intensive blood pressure (BP) lowering has been shown to improve functional outcome in acute intracerebral hemorrhage (ICH), but the treatment effect is modest and without a clearly defined underlying explanatory mechanism. We aimed at more reliably quantifying the benefits of this treatment according to different time periods in the recovery of participants in the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT) studies. Pooled analysis of the pilot INTERACT1 (n = 404) and main INTERACT2 (n = 2,839) involving patients with spontaneous ICH (patient characteristic subgroups, with trends favoring those randomized early, and with higher SBP and milder neurological severity at baseline. Intensive BP lowering provides beneficial effects on physical functioning that manifests consistently through the early and later phases of recovery from ICH. © 2015 S. Karger AG, Basel.

  8. Clinical usefulness of T1-201 myocardial scintigraphy and diastolic phase index by gated cardiac blood pool imaging in patients with hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Ohmine, Hiromi; Nishimura, Tsunehiko; Hayashida, Kohhei; Uehara, Toshiisa; Kozuka, Takahiro

    1984-01-01

    Tl-201 myocardial scintigraphy and gated cardiac blood pool imaging with Tc-99m were performed at rest in 24 hypertrophic cardiomyopathy (HCM) and 11 normal subjects. Based on visual analysis of Tl-201 myocardial scintigraphies, patients with HCM were subdivided into the following four groups; type I: non-obstructive, type II: obstructive, type III: asymmetric septal hypertrophy, type IV: apical hypertrophy. Characteristic myocardial hypertrophy of each group was also confirmed from the profile curves of circumferential analysis. First third filling fraction (1/3 FF) and mean first third filling rate (1/3 FRm) were obtained from gated cardiac blood pool imaging. As compaired with the normal subjects, 1/3 FF was not so sensitive for the detection of left ventricular hypertrophy. Mean+-S.D. of 1.3 FRm were 1.96+-0.56/sec (normal group), 1.30+-0.44/sec (typ e I), 1.18+-0.63/sec (type II), 1.17+-0.14/sec (type III), and 1.26+-0.03/sec (type IV). We considered that 1/3 FRm was a useful diastolic phase index in the diagnosis of HCM. (author)

  9. Exciting Pools

    Science.gov (United States)

    Wright, Bradford L.

    1975-01-01

    Advocates the creation of swimming pool oscillations as part of a general investigation of mechanical oscillations. Presents the equations, procedure for deriving the slosh modes, and methods of period estimation for exciting swimming pool oscillations. (GS)

  10. Wall morphology, blood flow and wall shear stress: MR findings in patients with peripheral artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Galizia, Mauricio S.; Barker, Alex; Collins, Jeremy; Carr, James [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Liao, Yihua [Northwestern University' s Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL (United States); McDermott, Mary M. [Northwestern University' s Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL (United States); Northwestern University' s Feinberg School of Medicine, Department of Medicine, Chicago, IL (United States); Markl, Michael [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Northwestern University, Department Biomedical Engineering, McCormick School of Engineering, Chicago, IL (United States)

    2014-04-15

    To investigate the influence of atherosclerotic plaques on femoral haemodynamics assessed by two-dimensional (2D) phase-contrast (PC) magnetic resonance imaging (MRI) with three-directional velocity encoding. During 1 year, patients with peripheral artery disease and an ankle brachial index <1.00 were enrolled. After institutional review board approval and written informed consent, 44 patients (age, 70 ± 12 years) underwent common femoral artery MRI. Patients with contra-indications for MRI were excluded. Sequences included 2D time-of-flight, proton-density, T1-weighted and T2-weighted MRI. Electrocardiogram (ECG)-gated 2D PC-MRI with 3D velocity encoding was acquired. A radiologist classified images in five categories. Blood flow, velocity and wall shear stress (WSS) along the vessel circumference were quantified from the PC-MRI data. The acquired images were of good quality for interpretation. There were no image quality problems related to poor ECG-gating or slice positioning. Velocities, oscillatory shear stress and total flow were similar between patients with normal arteries and wall thickening/plaque. Patients with plaques demonstrated regionally increased peak systolic WSS and enhanced WSS eccentricity. Combined multi-contrast morphological imaging of the peripheral arterial wall with PC-MRI with three-directional velocity encoding is a feasible technique. Further study is needed to determine whether flow is an appropriate marker for altered endothelial cell function, vascular remodelling and plaque progression. (orig.)

  11. 3D pulmonary perfusion MRI and MR angiography of pulmonary embolism in pigs after a single injection of a blood pool MR contrast agent

    International Nuclear Information System (INIS)

    Fink, Christian; Ley, Sebastian; Puderbach, Michael; Plathow, Christian; Kauczor, Hans-Ulrich; Bock, Michael

    2004-01-01

    The purpose of this study was to assess the feasibility of contrast-enhanced 3D perfusion MRI and MR angiography (MRA) of pulmonary embolism (PE) in pigs using a single injection of the blood pool contrast Gadomer. PE was induced in five domestic pigs by injection of autologous blood thrombi. Contrast-enhanced first-pass 3D perfusion MRI (TE/TR/FA: 1.0 ms/2.2 ms/40 ; voxel size: 1.3 x 2.5 x 4.0 mm 3 ; TA: 1.8 s per data set) and high-resolution 3D MRA (TE/TR/FA: 1.4 ms/3.4 ms/40 ; voxel size: 0.8 x 1.0 x 1.6 mm 3 ) was performed during and after a single injection of 0.1 mmol/kg body weight of Gadomer. Image data were compared to pre-embolism Gd-DTPA-enhanced MRI and post-embolism thin-section multislice CT (n=2). SNR measurements were performed in the pulmonary arteries and lung. One animal died after induction of PE. In all other animals, perfusion MRI and MRA could be acquired after a single injection of Gadomer. At perfusion MRI, PE could be detected by typical wedge-shaped perfusion defects. While the visualization of central PE at MRA correlated well with the CT, peripheral PE were only visualized by CT. Gadomer achieved a higher peak SNR of the lungs compared to Gd-DTPA (21±8 vs. 13±3). Contrast-enhanced 3D perfusion MRI and MRA of PE can be combined using a single injection of the blood pool contrast agent Gadomer. (orig.)

  12. Validation of Perfusion Quantification with 3D Gradient Echo Dynamic Contrast-Enhanced Magnetic Resonance Imaging Using a Blood Pool Contrast Agent in Skeletal Swine Muscle.

    Directory of Open Access Journals (Sweden)

    Stefan Hindel

    Full Text Available The purpose of our study was to validate perfusion quantification in a low-perfused tissue by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI with shared k-space sampling using a blood pool contrast agent. Perfusion measurements were performed in a total of seven female pigs. An ultrasonic Doppler probe was attached to the right femoral artery to determine total flow in the hind leg musculature. The femoral artery was catheterized for continuous local administration of adenosine to increase blood flow up to four times the baseline level. Three different stable perfusion levels were induced. The MR protocol included a 3D gradient-echo sequence with a temporal resolution of approximately 1.5 seconds. Before each dynamic sequence, static MR images were acquired with flip angles of 5°, 10°, 20°, and 30°. Both static and dynamic images were used to generate relaxation rate and baseline magnetization maps with a flip angle method. 0.1 mL/kg body weight of blood pool contrast medium was injected via a central venous catheter at a flow rate of 5 mL/s. The right hind leg was segmented in 3D into medial, cranial, lateral, and pelvic thigh muscles, lower leg, bones, skin, and fat. The arterial input function (AIF was measured in the aorta. Perfusion of the different anatomic regions was calculated using a one- and a two-compartment model with delay- and dispersion-corrected AIFs. The F-test for model comparison was used to decide whether to use the results of the one- or two-compartment model fit. Total flow was calculated by integrating volume-weighted perfusion values over the whole measured region. The resulting values of delay, dispersion, blood volume, mean transit time, and flow were all in physiologically and physically reasonable ranges. In 107 of 160 ROIs, the blood signal was separated, using a two-compartment model, into a capillary and an arteriolar signal contribution, decided by the F-test. Overall flow in hind leg muscles

  13. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting; Die EKG-getriggerte 4-Zeilen-Spiral-CT des Herzens in der praeoperativen Bildgebung vor minimalinvasiver koronarer Bypass-Operation

    Energy Technology Data Exchange (ETDEWEB)

    Begemann, P.G.C.; Ittrich, H.; Koops, A.; Adam, G.; Weber, C. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Radiologisches Zentrum, Universitaetsklinikum, Hamburg (Germany); Arnold, M.; Detter, C.; Boehm, D.H.; Reichenspurner, H. [Universitaetsklinikum Hamburg-Eppendorf, Herzzentrum, Herz und Gefaesschirurgie, Hamburg (Germany)

    2005-08-01

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  14. Critical appraisal and pooled analysis of telmisartan alone or in combination with hydrochlorothiazide for achieving blood pressure goals

    Directory of Open Access Journals (Sweden)

    Satoshi Morimoto

    2010-06-01

    Full Text Available Satoshi Morimoto, Nobuyuki Takahashi, Tatsuyori Morita, Kazunori Someya, Nagaoki Toyoda, Toshiji IwasakaSecond Department of Internal Medicine, Kansai Medical University 2-3-1, Shinmachi, Hirakata, Osaka 573-1191, JapanAbstract: Rigid control of blood pressure (BP is essential to prevent cardiovascular disease. However, only about 40% of hypertensive patients undergoing pharmacological intervention with a single agent achieve their BP goals in contemporary clinical practice. Combined therapy using currently available agents is effective in maximizing treatment outcome, although it raises medical costs and decreases the drug compliance rate. To overcome such negative consequences, a combination tablet containing an angiotensin II receptor blocker (ARB with a small dose of hydrochlorothiazide (HCTZ is now available on the international market, including Japan. This article briefly describes the unique properties of telmisartan, a highly selective ARB for the angiotensin II type 1 receptor, including its long-acting characteristics and recent prospective multicenter randomized clinical trials, followed by a description of a newly-introduced combination tablet in Japan, which contains telmisartan and HCTZ. This article also reviews its safety and efficacy based on currently available evidence. Finally, evidence comparing telmisartan/HCTZ with other combination therapies is presented.Keywords: angiotensin II receptor blocker, ARB, blood pressure, hypertension, diuretics, PPAR-γ

  15. Subtraction imaging of the ECG gated cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Tanegashima, K.; Fukui, M.; Hyodo, H.

    1987-05-01

    The subtracting manipulation of contrast-enhanced gated cardiac CT (GCCT) images was experimentally studied with TCT 60A - 30 type (Toshiba) for clinical use, thereby reducing the amount of contrast medium (CM). Initially the optimum relationship between the concentration of CM and its injected velocity was determined using the model of resected canine hearts and in actual dogs. The emphasized good-subtracted images were obtained when the difference of CT values was approximately 40 H.U. between cardiac cavity and myocardium. Such condition was feasible in the use of 25 % Diatrizoic acid and its injected velocity of 0.02 ml/kg/sec. Finally the reduction of the amount of CM by 1/3 became possible in clinical settings. The method is applicable to multi-slice GCCT in various heart diseases.

  16. Comparison of exercise blood pressure measured by technician and an automated system.

    Science.gov (United States)

    Garcia-Gregory, J A; Jackson, A S; Studeville, J; Squires, W G; Owen, C A

    1984-05-01

    We evaluated the automated system Blood Pressure Measuring System (BPMS) developed by NASA on 277 adult males who elected to have a treadmill test as part of their annual physical. The BPMS uses acoustic transduction with a computer-assisted ECG gating to detect nonsynchronous noise. The BPMS readings were compared to pressures simultaneously measured by trained technicians. For all stages of work, BPMS readings were higher for systolic and lower for diastolic than technician readings. At peak stages of work, BPMS systolic pressures were about 20 mmHg higher than technician readings. Within each 3-min workstage, BPMS readings were found to be more inconsistent than technician readings. The standard errors of measurement for BPMS were from two to three times higher than technician values. These data showed automated blood pressure readings were significantly different than technician values and subject to more random fluctuations. These findings demonstrate the need to view exercise blood pressure measured by automated systems with caution.

  17. Assessment of various systolic phase indexes for the detection of coronary artery disease by multi-gated blood pool imaging at rest

    International Nuclear Information System (INIS)

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa; Honda, Minoru; Kanao, Keisuke

    1982-01-01

    After Tc-99m was labeled with red blood cells in vivo, multi-gated blood pool imaging (MGBPI) was obtained at anterior and 40-degree left anterior oblique (LAO) position at rest. In addition to left ventricular (LV) ejection fraction (EF) and wall motion (WM) abnormality, first-third EF, mean normalized systolic ejection rate, SdV/dt/EDV (LV peak ejection rate normalized by end-diastolic volume) and SdV/dt/V (peak ejection rate normalized by LV volume at the peak ejection) were calculated. Patients were divided into 3 groups; Normal (n = 14), coronary artery disease (CAD) with normal EF (> = 55%) and normal WM (Group I, n = 16), and CAD with abnormal EF and/or WM abnormality (Group II, n = 31). In all subjects of Normal and 13 patients of Group I, graded supine exercise stress MGBPI was performed at LAO position by using bicycle ergometer. All systolic phase indexes were correlated well with EF (r > = 0.77, p - 1 , p - 1 as a criteria of CAD, sensitivity of this index was 91% (100% in Group II and 75% in Group I). This sensitivity in Group I was identical with that of exercise stress MGBPI. Specificity of SdV/dt/V (86%) was a little inferior to that of exercise stress MGBPI (93%), but it was not statistically significant. In conclusion, SdV/dt/V is a useful systolic phase index to detect CAD. (J.P.N.)

  18. Does Preinterventional Flat-Panel Computer Tomography Pooled Blood Volume Mapping Predict Final Infarct Volume After Mechanical Thrombectomy in Acute Cerebral Artery Occlusion?

    International Nuclear Information System (INIS)

    Wagner, Marlies; Kyriakou, Yiannis; Mesnil de Rochemont, Richard du; Singer, Oliver C.; Berkefeld, Joachim

    2013-01-01

    PurposeDecreased cerebral blood volume is known to be a predictor for final infarct volume in acute cerebral artery occlusion. To evaluate the predictability of final infarct volume in patients with acute occlusion of the middle cerebral artery (MCA) or the distal internal carotid artery (ICA) and successful endovascular recanalization, pooled blood volume (PBV) was measured using flat-panel detector computed tomography (FPD CT).Materials and MethodsTwenty patients with acute unilateral occlusion of the MCA or distal ACI without demarcated infarction, as proven by CT at admission, and successful Thrombolysis in cerebral infarction score (TICI 2b or 3) endovascular thrombectomy were included. Cerebral PBV maps were acquired from each patient immediately before endovascular thrombectomy. Twenty-four hours after recanalization, each patient underwent multislice CT to visualize final infarct volume. Extent of the areas of decreased PBV was compared with the final infarct volume proven by follow-up CT the next day.ResultsIn 15 of 20 patients, areas of distinct PBV decrease corresponded to final infarct volume. In 5 patients, areas of decreased PBV overestimated final extension of ischemia probably due to inappropriate timing of data acquisition and misery perfusion.ConclusionPBV mapping using FPD CT is a promising tool to predict areas of irrecoverable brain parenchyma in acute thromboembolic stroke. Further validation is necessary before routine use for decision making for interventional thrombectomy

  19. ROC Analysis of Visual Assessments Made in Gated Blood Pool Scans of Patients with Coronary Artery Disease

    International Nuclear Information System (INIS)

    Lee, Kyung Han; Choi, Yoon Ho; Lee, Bum Woo; Moon, Dae Hyuk; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Koong, Sung Soo

    1989-01-01

    Visual assessment of regional wall motion abnormality (RWMA) by gated blood pol scan (GBPS) serves as an useful parameter in thc diagnosis, functional evaluation, and follow up in various clinical settings, but are still subject to some inherent limitations. On important problem may be the interobserver as well as intraobsever variation that may well be present due to the subjective nature of the interpretations. This study was carried out to determine the reliability and reproducibility of visual assessments made in GBPSs, and to observe the degree to which the results would be influenced by observer variation. Fifty two patients with coronary heart disease had resting GBPS and contrast ventriculography within 4 days apart. Contrast ventriculography showed normal wall motion in 6 patients and the remaining 46 had RWMA in one or more segments. The anterior and left anterolateral views of all 52 GBPSs were analyzed by three independent observers, who selected from 5 scales, their level of confidence that there was RWMA in that segment. Receiver operating characteristic (ROC) curves for each analysis was plotted and the area under the curve (θ) was used as a parameter representing each observer's performance in his interpretations. The findings of contract ventriculographies were used as the standard for RWMA. The apical and inferoapical segments showed the best correlation with contrast ventriculography (θ=0.90-.094, 0.81-0.94, respectively), and the inferior wall showed the poorest correlation (θ=0.70-0.74). The interpretations of the inferior, septal, apical and posteroinferior, segments showed no difference between the observers, but there was significantly better performance in assessment by observer A compared to that by B or C for the anterolateral segments (θ=0.87, 0.78, 0.76, respectively, p<0.01 for A vs B, p<0,05 for A vs C), as well as when all segments were considered altogether (θ=0,88, 0.83, 0.82, respectively, both p<0 05). This was also true for

  20. Semi-automatic segmentation of gated blood pool emission tomographic images by watersheds: application to the determination of right and left ejection fractions

    International Nuclear Information System (INIS)

    Mariano-Goulart, D.; Collet, H.; Kotzki, P.-O.; Zanca, M.; Rossi, M.

    1998-01-01

    Tomographic multi-gated blood pool scintigraphy (TMUGA) is a widely available method which permits simultaneous assessment of right and left ventricular ejection fractions. However, the widespread clinical use of this technique is impeded by the lack of segmentation methods dedicated to an automatic analysis of ventricular activities. In this study we evaluated how a watershed algorithm succeeds in providing semi-automatic segmentation of ventricular activities in order to measure right and left ejection fractions by TMUGA. The left ejection fractions of 30 patients were evaluated both with TMUGA and with planar multi-gated blood pool scintigraphy (PMUGA). Likewise, the right ejection fractions of 25 patients were evaluated with first-pass scintigraphy (FP) and with TMUGA. The watershed algorithm was applied to the reconstructed slices in order to group together the voxels whose activity came from one specific cardiac cavity. First, the results of the watershed algorithm were compared with manual drawing around left and right ventricles. Left ejection fractions evaluated by TMUGA with the watershed procedure were not significantly different (p=0.30) from manual outlines whereas a small but significant difference was found for right ejection fractions (p=0.004). Then right and left ejection fractions evaluated by TMUGA (with the semi-automatic segmentation procedure) were compared with the results obtained by FP or PMUGA. Left ventricular ejection fractions evaluated by TMUGA showed an excellent correlation with those evaluated by PMUGA (r=0.93; SEE=5.93%; slope=0.99; intercept = 4.17%). The measurements of these ejection fractions were significantly higher with TMUGA than with PMUGA (P<0.01). The interoperator variability for the measurement of left ejection fractions by TMUGA was 4.6%. Right ventricular ejection fractions evaluated by TMUGA showed a good correlation with those evaluated by FP (r = 0.81; SEE = 6.68%; slope = 1.00; intercept = 0.85%) and were not

  1. Assessment of right ventricular function using gated blood pool single photon emission computed tomography in inferior myocardial infarction with or without hemodynamically significant right ventricular infarction

    International Nuclear Information System (INIS)

    Takahashi, Masaharu

    1992-01-01

    Right ventricular function was assessed using gated blood pool single photon emission computed tomography (GSPECT) in 10 normal subjects and 14 patients with inferior myocardial infarction. Three-dimensional backbround subtraction was achieved by applying an optimal cut off level. The patient group consisted of 6 patients with definite hemodynamic abnormalities indicative of right ventricular infarction (RVI) and 8 other patients with significant obstructive lesion at the proximal portion of right coronary artery without obvious hemodynamic signs of RVI. Right ventricular regional wall motion abnormalities were demonstrated on GSPECT functional images and the indices of right ventricular function (i.e the right ventricular ejection fraction (RVEF), the right ventricular peak ejection rate (RVPER) and the right ventricular peak filling rate (RVPFR)) were significantly reduced in the patient group, not only in the patients with definite RVI but also in those without hemodynamic signs of RVI, even in the absence of definite hemodynamic signs, when the proximal portion of right coronary artery is obstructed. It is concluded that GSPECT is reliable for the assessment of right ventricular function and regional wall motion, and is also useful for the diagnosis of RVI. (author)

  2. Magnetic resonance characterization of tumor microvessels in experimental breast tumors using a slow clearance blood pool contrast agent (carboxymethyldextran-A2-Gd-DOTA) with histopathological correlation

    International Nuclear Information System (INIS)

    Preda, Anda; Novikov, Viktor; Moeglich, Martina; Turetschek, Karl; Shames, David M.; Roberts, Timothy P.L.; Brasch, Robert C.; Floyd, Eugenia; Carter, Wayne O.; Corot, Claire

    2005-01-01

    Carboxymethyldextran (CMD)-A2-Gd-DOTA, a slow clearance blood pool contrast agent with a molecular weight of 52.1 kDa, designed to have intravascular residence for more than 1 h, was evaluated for its potential to characterize and differentiate the microvessels of malignant and benign breast tumors. Precontrast single-slice inversion-recovery snapshot FLASH and dynamic contrast-enhanced MRI using an axial T1-weighted three-dimensional spoiled gradient recalled sequence was performed in 30 Sprague-Dawley rats with chemically induced breast tumors. Endothelial transfer coefficient and fractional plasma volume of the breast tumors were estimated from MRI data acquired with CMD-A2-Gd-DOTA enhancement injected at a dose of 0.1 mmol Gd/kg body weight using a two-compartment bidirectional model of the tumor tissue. The correlation between MRI microvessel characteristics and histopathological tumor grade was determined using the Scarff-Bloom-Richardson method. Using CMD-A2-Gd-DOTA, no significant correlations were found between the MR-estimated endothelial transfer coefficient or plasma volumes with histological tumor grade. Analysis of CMD-A2-Gd-DOTA-enhanced MR kinetic data failed to demonstrate feasibility for the differentiation of benign from malignant tumors or for image-based tumor grading. (orig.)

  3. Ultrashort Echo Time Magnetic Resonance Imaging of the Lung Using a High-Relaxivity T1 Blood-Pool Contrast Agent

    Directory of Open Access Journals (Sweden)

    Joris Tchouala Nofiele

    2014-10-01

    Full Text Available The lung remains one of the most challenging organs to image using magnetic resonance imaging (MRI due to intrinsic rapid signal decay. However, unlike conventional modalities such as computed tomography, MRI does not involve radiation and can provide functional and morphologic information on a regional basis. Here we demonstrate proof of concept for a new MRI approach to achieve substantial gains in a signal to noise ratio (SNR in the lung parenchyma: contrast-enhanced ultrashort echo time (UTE imaging following intravenous injection of a high-relaxivity blood-pool manganese porphyrin T1 contrast agent. The new contrast agent increased relative enhancement of the lung parenchyma by over 10-fold compared to gadolinium diethylene triamine pentaacetic acid (Gd-DTPA, and the use of UTE boosted the SNR by a factor of 4 over conventional T1-weighted gradient echo acquisitions. The new agent also maintains steady enhancement over at least 60 minutes, thus providing a long time window for obtaining high-resolution, high-quality images and the ability to measure a number of physiologic parameters.

  4. Routine measurements of left and right ventricular output by gated blood pool emission tomography in comparison with thermodilution measurements: a preliminary study

    International Nuclear Information System (INIS)

    Mariano-Goulart, D.; Boudousq, V.; Comte, F.; Eberle, M.C.; Zanca, M.; Kotzki, P.O.; Rossi, M.; Piot, C.; Raczka, F.; Davy, J.M.

    2001-01-01

    The aim of this preliminary study was to evaluate the accuracy of left and right ventricular output computed from a semi-automatic processing of tomographic radionuclide ventriculography data (TRVG) in comparison with the conventional thermodilution method. Twenty patients with various heart diseases were prospectively included in the study. Thermodilution and TRVG acquisitions were carried out on the same day for all patients. Analysis of gated blood pool slices was performed using a watershed-based segmentation algorithm. Right and left ventricular output measured by TRVG correlated well with the measurements obtained with thermodilution (r=0.94 and 0.91 with SEE=0.38 and 0.46 l/min, respectively, P<0.001). The limits of agreement for TRVG and thermodilution measurements were -0.78-1.20 l/min for the left ventricle and -0.34-1.16 l/min for the right ventricle. No significant difference was found between the results of TRVG and thermodilution with respect to left ventricular output (P=0.09). A small but significant difference was found between right ventricular output measured by TRVG and both left ventricular output measured by TRVG (mean difference=0.17 l/min, P=0.04) and thermodilution-derived cardiac output (mean difference=0.41 l/min, P=0.0001). It is concluded that the watershed-based semi-automatic segmentation of TRVG slices provides non-invasive measurements of right and left ventricular output and stroke volumes at equilibrium, in routine clinical settings. Further studies are necessary to check whether the accuracy of these measurements is good enough to permit correct assessment of intracardiac shunts. (orig.)

  5. High-resolution blood-pool-contrast-enhanced MR angiography in glioblastoma: tumor-associated neovascularization as a biomarker for patient survival. A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Puig, Josep; Blasco, Gerard; Remollo, Sebastian; Hernandez, David; Pedraza, Salvador [Hospital Universitari Dr Josep Trueta, Research Unit of Diagnostic Imaging Institute (IDI), Department of Radiology [Girona Biomedical Research Institute] IDIBGI, Girona (Spain); Daunis-i-Estadella, Josep; Mateu, Gloria [University of Girona, Department of Computer Science, Applied Mathematics and Statistics, Girona (Spain); Alberich-Bayarri, Angel [La Fe Polytechnics and University Hospital, Biomedical Imaging Research Group (GIBI230), La Fe Health Research Institute, Valencia (Spain); Essig, Marco [University of Manitoba, Department of Radiology, Winnipeg (Canada); Jain, Rajan [NYU School of Medicine, Division of Neuroradiology, Department of Radiology, New York, NY (United States); Puigdemont, Montserrat [Hospital Universitari Dr Josep Trueta, Catalan Institute of Oncology (ICO), Hospital Cancer Registry, Girona (Spain); Sanchez-Gonzalez, Javier [Philips Healthcare Iberica, Madrid (Spain); Wintermark, Max [Stanford University, Department of Radiology, Neuroradiology Division, Palo Alto, CA (United States)

    2016-01-15

    The objective of the study was to determine whether tumor-associated neovascularization on high-resolution gadofosveset-enhanced magnetic resonance angiography (MRA) is a useful biomarker for predicting survival in patients with newly diagnosed glioblastomas. Before treatment, 35 patients (25 men; mean age, 64 ± 14 years) with glioblastoma underwent MRI including first-pass dynamic susceptibility contrast (DSC) perfusion and post-contrast T1WI sequences with gadobutrol (0.1 mmol/kg) and, 48 h later, high-resolution MRA with gadofosveset (0.03 mmol/kg). Volumes of interest for contrast-enhancing lesion (CEL), non-CEL, and contralateral normal-appearing white matter were obtained, and DSC perfusion and DWI parameters were evaluated. Prognostic factors were assessed by Kaplan-Meier survival and Cox proportional hazards model. Eighteen (51.42 %) glioblastomas were hypervascular on high-resolution MRA. Hypervascular glioblastomas were associated with higher CEL volume and lower Karnofsky score. Median survival rates for patients with hypovascular and hypervascular glioblastomas treated with surgery, radiotherapy, and chemotherapy were 15 and 9.75 months, respectively (P < 0.001). Tumor-associated neovascularization was the best predictor of survival at 5.25 months (AUC = 0.794, 81.2 % sensitivity, 77.8 % specificity, 76.5 % positive predictive value, 82.4 % negative predictive value) and yielded the highest hazard ratio (P < 0.001). Tumor-associated neovascularization detected on high-resolution blood-pool-contrast-enhanced MRA of newly diagnosed glioblastoma seems to be a useful biomarker that correlates with worse survival. (orig.)

  6. Effect of biventricular pacing on heart function evaluated by gated blood pool study in patients with end-stage heart failure

    International Nuclear Information System (INIS)

    Cholewinski, W.; Tarkowska, A.; Stefaniak, B.; Poniatowicz-Frasunek, E.; Kutarski, A.; Oleszczak, K.

    2002-01-01

    Biventricular cardiac pacing has been used as a complementary form of therapy in patients with severe heart failure. The aim of this study was to evaluate the effect of the synchronous stimulation of both ventricles on the heart function measured by gated blood pool study (GBP). Ten patients (9 men and 1 woman aged 53-74 years) with end-stage heart failure (HF) were studied. In all patients long-term biventricular pacing (BV) was applied. The obtained results were compared with single-chamber stimulation in 5 patients and with sinus rhythm (SR) in 8 patients. All patients underwent repeated GBP with RBC labelled with 740 MBq of 99m Tc-pertechnetate. The LVEF was calculated according to the standard method based on the count rates. Phase analysis was performed with the standard method using first Fourier element. Clinically in almost all patients moderate to important symptomatic improvement has been observed. The analysis of LVEF values revealed that BV pacing resulted in significantly higher values only in comparison with SR (21.6% ±10.3 v. 20.1% ± 10.1; p o± 29.6 v. 13.4 o± 37.6 and 7.4 o± 26.5 v. 6.0 o± 17.1, respectively). However, in comparison with LV pacing, BV stimulation revealed a change of dominant conduction abnormalities with a delay of RV contraction in relation to LV (9.0 o± 17.5 v. -3.0 o± 11.4). Biventricular pacing results in slight improvement of LVEF in patients with heart failure and can be considered a promising approach in patients with end-stage heart failure. Synchronous stimulation of both ventricles not always results in decrease of interventricular shift, however that observation requires further studies on a larger population. (author)

  7. Malaria diagnosis from pooled blood samples: comparative analysis of real-time PCR, nested PCR and immunoassay as a platform for the molecular and serological diagnosis of malaria on a large-scale

    Directory of Open Access Journals (Sweden)

    Giselle FMC Lima

    2011-09-01

    Full Text Available Malaria diagnoses has traditionally been made using thick blood smears, but more sensitive and faster techniques are required to process large numbers of samples in clinical and epidemiological studies and in blood donor screening. Here, we evaluated molecular and serological tools to build a screening platform for pooled samples aimed at reducing both the time and the cost of these diagnoses. Positive and negative samples were analysed in individual and pooled experiments using real-time polymerase chain reaction (PCR, nested PCR and an immunochromatographic test. For the individual tests, 46/49 samples were positive by real-time PCR, 46/49 were positive by nested PCR and 32/46 were positive by immunochromatographic test. For the assays performed using pooled samples, 13/15 samples were positive by real-time PCR and nested PCR and 11/15 were positive by immunochromatographic test. These molecular methods demonstrated sensitivity and specificity for both the individual and pooled samples. Due to the advantages of the real-time PCR, such as the fast processing and the closed system, this method should be indicated as the first choice for use in large-scale diagnosis and the nested PCR should be used for species differentiation. However, additional field isolates should be tested to confirm the results achieved using cultured parasites and the serological test should only be adopted as a complementary method for malaria diagnosis.

  8. Pool scrubbing

    International Nuclear Information System (INIS)

    Lopez-Jimenez, J.; Herranz, J.; Escudero, M.J.; Espigares, M.M.; Peyres, V.; Polo, J.; Kortz, Ch.; Koch, M.K.; Brockmeier, U.; Unger, H.; Dutton, L.M.C.; Smedley, Ch.; Trow, W.; Jones, A.V.; Bonanni, E.; Calvo, M.; Alonso, A.

    1996-12-01

    The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

  9. Comprehensive MRA of the lower limbs including high-resolution extended-phase infra-inguinal imaging with gadobenate dimeglumine: Initial experience with inter-individual comparison to the blood-pool contrast agent gadofosveset trisodium

    International Nuclear Information System (INIS)

    Christie, A.; Chandramohan, S.; Roditi, G.

    2013-01-01

    Aim: To compare extended-phase imaging using an extracellular space contrast agent, gadobenate dimeglumine, to imaging with a blood-pool contrast agent, gadofosveset, for magnetic resonance angiography. Materials and methods: A lower-limb magnetic resonance angiography (MRA) protocol (dynamic crural, three-station bolus chase, and infra-inguinal high resolution) designed for blood-pool agent imaging was adapted for use with the extracellular agent, gadobenate dimeglumine, primarily by using a triphasic injection protocol. Ten patients scanned with gadofosveset were compared to 10 patients scanned with gadobenate. The dynamic, bolus chase, and high-resolution images were scored for quality on a Likert scale (from 1–5). Signal- and contrast-to-noise ratios were analysed, and Mann–Whitney U statistical analysis performed. Results: There was no significant difference for the dynamic imaging or the aorto-iliac station of the bolus chase. Infra-inguinal bolus chase images were higher quality (p < 0.05 Mann–Whitney U test) with gadobenate. Signal analysis confirmed lower signal and contrast for venous imaging on the high spatial resolution acquisitions with gadobenate; however, this allowed improved arterial conspicuity. Conclusion: Extended-phase imaging using an extracellular space contrast agent is feasible and provides image quality to equal imaging with a blood-pool contrast agent.

  10. Radiosynoviorthesis in hemophilic arthropathy: pathologic blood pool imaging on pre-therapeutic bone scintigraphy is not a predictor of treatment success

    Energy Technology Data Exchange (ETDEWEB)

    Sabet, Amir [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); University Hospital, Department of Nuclear Medicine, Bonn (Germany); Strauss, Andreas Christian; Schmolders, Jan; Bornemann, Rahel; Pennekamp, Peter Hans [University of Bonn, Department of Orthopaedics and Trauma Surgery, Bonn (Germany); Sabet, Amin; Biersack, Hans Juergen [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Oldenburg, Johannes [University of Bonn, Department of Experimental Hematology and Transfusion Medicine, Bonn (Germany); Ezziddin, Samer [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Saarland University, Department of Nuclear Medicine, Homburg (Germany)

    2017-03-15

    Increased articular {sup 99m}Tc MDP uptake on blood pool imaging (BPI) of patients with rheumatologic conditions is indicative of active inflammatory changes, and has been suggested as a strong predictor of response to radiosynoviorthesis (RSO). In this study, we aimed to assess the value of pretreatment BPI positivity (i.e. scintigraphic-apparent hyperemia) for successful RSO in hemophilic arthropathy. Thirty-four male patients with painful hemophilic arthropathy underwent RSO after failure of conservative treatment. Treated joints comprised the knee in eight, elbow in five, and ankle in 21 patients. Pretreatment triple-phase bone scintigraphy showed hyperemic joints (pathologic BPI) in 17 patients, whereas 17 patients had no increased tracer uptake on BPI. Response to RSO was evaluated 6 months post-treatment by measuring changes in intensity of arthralgia according to the visual analog scale (VAS), bleeding frequency, and range of motion. The association between hyperemia (pathologic BPI) and treatment outcome was examined using nonparametric tests for independent samples. Clinically evident pain relief occurred in 26 patients (76.5 %), and the mean VAS decreased from 7.7 ± 1.1 to 4.6 ± 2.7 (p < 0.001). Joint bleeding frequency (hemarthrosis) decreased from 4.5 ± 0.6 to 2.1 ± 0.4 during the first 6 months after RSO (p < 0.001). For both parameters (pain relief and bleeding frequency), patients experienced a similar benefit from RSO regardless of pretreatment BPI: arthralgia (p = 0.312) and frequency of hemarthrosis (p = 0.396). No significant improvement was observed for range of motion, but it was significantly more restricted in hyperemic joints both before (p = 0.036) and after treatment (p = 0.022). Hemophilic arthropathy can be effectively treated with RSO regardless of pre-therapeutic BPI. Patients in whom articular hyperemia is not detectable by scintigraphy may have similar (outstanding) outcomes, and thus should not be excluded from treatment. (orig.)

  11. Evaluation of right ventricular function using gated equilibrium blood pool radionuclide ventriculography in patients with congenital volume and pressure overload late after surgical repair

    International Nuclear Information System (INIS)

    Hirata, Nobuaki; Sakakibara, Tetsuo; Watanabe, Shinichiro; Nomura, Fumikazu; Akamatsu, Hiroki; Matsumura, Yasushi; Yamamoto, Kazuhiro; Sasaki, Jiro; Kodama, Kazuhisa

    1991-01-01

    The effects of congenital right ventricular pressure and volume overload were studied in 3 patients with pulmonary stenosis, 7 with atrial septal defect and 6 with atrial septal defect plus pulmonary stenosis late after successful surgical correction. Gated equilibrium blood pool radionuclide ventriculography was used to measure right ventricular function at rest and during exercise and to compare it with eight normal subjects. Right ventricular ejection fractions at rest and during exercise were measured to be 61±9% and 66±13%, respectively, in the group with pulmonary stenosis, 49±7% and 54±8% in the group with atrial septal defect, and 65±13% and 69±13% in the group with atrial septal defect plus pulmonary stenosis. The values in the groups with pulmonary stenosis and atrial septal defect plus pulmonary stenosis were significantly higher than the control subjects (45±5% and 51±5%, p<0.01). The peak filling rate at rest and during exercise was also significantly higher in the groups with pulmonary stenosis and atrial septal defect plus pulmonary stenosis than in controls (at rest, 2.72±0.72, 2.53±0.94 vs. 1.64±0.24 p<0.05; during exercise, 4.38±1.23, 4.13±1.18 vs. 2.25±0.62, p<0.01). When patients with right ventricular systolic pressure equal to or greater than left ventricular systolic pressure and those with right ventricular systolic pressure less than left ventricular systolic pressure were compared, the right ventricular ejection fraction and peak filling rate were greater with the higher pressure at rest (71±10% and 3.12±0.81% vs. 55±3% and 2.30±0.27, p<0.05) and during exercise (75±11% and 4.86±1.01 vs. 59±3% and 2.61±0.35, p<0.05). Postoperative right ventricular hyperfunction may be due to preoperative pressure, but not volume, overload. (author)

  12. Phase analysis of gated blood pool SPECT for multiple stress testing assessments of ventricular mechanical dyssynchrony in a tachycardia-induced dilated cardiomyopathy canine model.

    Science.gov (United States)

    Salimian, Samaneh; Thibault, Bernard; Finnerty, Vincent; Grégoire, Jean; Harel, François

    2017-02-01

    Stress-induced dyssynchrony has been shown to be independently correlated with clinical outcomes in patients with dilated cardiomyopathy (DCM) and narrow QRS complexes. However, the extent to which stress levels affect inter- and intraventricular dyssynchrony parameters remains unknown. Ten large dogs were submitted to tachycardia-induced DCM by pacing the right ventricular apex for 3-4 weeks to reach a target ejection fraction (EF) of 35% or less. Stress was then induced in DCM dogs by administering intravenous dobutamine up to a maximum of 20 μg·kg -1 ·min -1 . Hemodynamic and ventricular dyssynchrony data were analyzed by left ventricular (LV) pressure measurements and gated blood pool SPECT (GBPS) imaging. In order to assess mechanical dyssynchrony in DCM subjects and compare it with that of 8 normal counterparts, we extracted the following data: count-based indices of LV contraction homogeneity index (CHI), entropy and phase standard deviation, and interventricular dyssynchrony index. A significant LV intraventricular dyssynchrony (CHI: 96.4 ± 1.3% in control vs 78.6% ± 10.9% in DCM subjects) resulted in an intense LV dysfunction in DCM subjects (EF: 49.5% ± 8.4% in control vs 22.6% ± 6.0% in DCM), compared to control subjects. However, interventricular dyssynchrony did not vary significantly between the two groups. Under stress, DCM subjects showed a significant improvement in ventricular functional parameters at each level (EF: 22.6% ± 6.0% at rest vs 48.1% ± 5.8% at maximum stress). All intraventricular dyssynchrony indices showed a significant increase in magnitude of synchrony from baseline to stress levels of greater than or equal to 5 μg·kg -1 ·min -1 dobutamine. There were individual differences in the magnitude and pattern of change in interventricular dyssynchrony during the various levels of stress. Based on GBPS analyses, different levels of functional stress, even in close intervals, can have a significant impact on

  13. Comparison of gated blood pool SPECT and spiral multidetector computed tomography in the assessment of right ventricular functional parameters. Validation with first-pass radionuclide angiography

    International Nuclear Information System (INIS)

    Lee, Jung S.; Kim, Seong-Jang; Kim, In-Ju; Kim, Yong-Ki; Choo, Ki S.; Lee, Jun S.

    2007-01-01

    The aim of this study was to compare gated blood pool single photon emission computed tomography (SPECT) (GBPS) and multidetector row computed tomography (MDCT) for the determination of right ventricular ejection fraction (RVEF) and right ventricular volumes (RVV) and to compare first-pass radionuclide angiography (FP-RNA) as the gold standard. Twenty consecutive patients (11 men, 9 women) referred for MDCT for the evaluation of the presence of coronary artery disease underwent FP-RNA and GBPS. The mean right ventricular end-diastolic volume (EDV) calculated with GBPS revealed a statistically significant lower value than that of MDCT. The mean right ventricular end-systolic volume (ESV) calculated with GBPS was also lower than that of MDCT. A comparison of right ventricular EDV from GBPS and MDCT yielded a correlation coefficient of 0.5972. Right ventricular ESV between GBPS and MDCT showed a correlation coefficient of 0.5650. The mean RVEFs calculated with FP-RNA (39.8%±4.0%), GBPS (43.7%±6.9%), and MDCT (40.4%±7.7%) showed no statistical differences (Kruskal-Wallis statistics 4.538, P=0.1034). A comparison of RVEFs from FP-RNA and GBPS yielded a correlation coefficient of 0.7251; RVEFs between FP-RNA and MDCT showed a correlation coefficient of 0.6166 and between GBPS and MDCT showed a correlation coefficient of 0.6367. The RVEF, EDV, and ESV calculated by GBPS had good correlation with those obtained with MDCT. In addition, there were no statistical differences of RVEF calculated from FP-RNA, GBPS, and MDCT. However, with regard to RVV, EDV and ESV from GBPS revealed statistically significantly lower values than those of MDCT. Although reasonable correlations among these modalities were obtained, the agreement among these three modalities was not good enough for interchangeable use in the clinical setting. Also, these results should be confirmed in patients with cardiac diseases in future larger population-based studies. (author)

  14. Worldwide trends in blood pressure from 1975 to 2015: a pooled analysis of 1479 population-based measurement studies with 19.1 million participants

    NARCIS (Netherlands)

    Zhou, Bin; Bentham, James; Di Cesare, Mariachiara; Bixby, Honor; Danaei, Goodarz; Cowan, Melanie J.; Paciorek, Christopher J.; Singh, Gitanjali; Hajifathalian, Kaveh; Bennett, James E.; Taddei, Cristina; Bilano, Ver; Carrillo-Larco, Rodrigo M.; Djalalinia, Shirin; Khatibzadeh, Shahab; Lugero, Charles; Peykari, Niloofar; Zhang, Wan Zhu; Lu, Yuan; Stevens, Gretchen A.; Riley, Leanne M.; Bovet, Pascal; Elliott, Paul; Gu, Dongfeng; Ikeda, Nayu; Jackson, Rod T.; Joffres, Michel; Kengne, Andre Pascal; Laatikainen, Tiina; Lam, Tai Hing; Laxmaiah, Avula; Liu, Jing; Miranda, J. Jaime; Mondo, Charles K.; Neuhauser, Hannelore K.; Sundstrom, Johan; Smeeth, Liam; Soric, Maroje; Woodward, Mark; Ezzati, Majid; Abarca-Gomez, Leandra; Abdeen, Ziad A.; Rahim, Hanan Abdul; Abu-Rmeileh, Niveen M.; Acosta-Cazares, Benjamin; Adams, Robert; Aekplakorn, Wichai; Afsana, Kaosar; Aguilar-Salinas, Carlos A.; Agyemang, Charles; Ahmadvand, Alireza; Ahrens, Wolfgang; Al Raddadi, Rajaa; Al Woyatan, Rihab; Ali, Mohamed M.; Alkerwi, Ala'a; Aly, Eman; Amouyel, Philippe; Amuzu, Antoinette; Andersen, Lars Bo; Anderssen, Sigmund A.; Angquist, Lars; Anjana, Ranjit Mohan; Ansong, Daniel; Aounallah-Skhiri, Hajer; Araujo, Joana; Ariansen, Inger; Aris, Tahir; Arlappa, Nimmathota; Aryal, Krishna; Arveiler, Dominique; Assah, Felix K.; Assuncao, Maria Cecilia F.; Avdicova, Maria; Azevedo, Ana; Azizi, Fereidoun; Babu, Bontha V.; Bahijri, Suhad; Balakrishna, Nagalla; Bandosz, Piotr; Banegas, Jose R.; Barbagallo, Carlo M.; Barcelo, Alberto; Barkat, Amina; Barros, Aluisio J. D.; Barros, Mauro V.; Bata, Iqbal; Batieha, Anwar M.; Baur, Louise A.; Beaglehole, Robert; Ben Romdhane, Habiba; Benet, Mikhail; Benson, Lowell S.; Bernabe-Ortiz, Antonio; Bernotiene, Gailute; Bettiol, Heloisa; Bhagyalaxmi, Aroor; Bharadwaj, Sumit; Bhargava, Santosh K.; Bi, Yufang; Bikbov, Mukharram; Bjerregaard, Peter; Bjertness, Espen; Bjokelund, Cecilia; Blokstra, Anneke; Bo, Simona; Bobak, Martin; Boeing, Heiner; Boggia, Jose G.; Boissonnet, Carlos P.; Bongard, Vanina; Braeckman, Lutgart; Brajkovich, Imperia; Branca, Francesco; Breckenkamp, Juergen; Brenner, Hermann; Brewster, Lizzy M.; Bruno, Graziella; Bueno-de-Mesquita, H. B. (as); Bugge, Anna; Burns, Con; Bursztyn, Michael; de Leon, Antonio Cabrera; Cameron, Christine; Can, Gunay; Candido, Ana Paula C.; Capuano, Vincenzo; Cardoso, Viviane C.; Carlsson, Axel C.; Carvalho, Maria J.; Casanueva, Felipe F.; Casas, Juan-Pablo; Caserta, Carmelo A.; Chamukuttan, Snehalatha; Chan, Angelique W.; Chan, Queenie; Chaturvedi, Himanshu K.; Chaturvedi, Nishi; Chen, Chien-Jen; Chen, Fangfang; Chen, Huashuai; Chen, Shuohua; Chen, Zhengming; Cheng, Ching-Yu; Dekkaki, Imane Cherkaoui; Chetrit, Angela; Chiolero, Arnaud; Chiou, Shu-Ti; Chirita-Emandi, Adela; Cho, Belong; Cho, Yumi; Chudek, Jerzy; Cifkova, Renata; Claessens, Frank; Clays, Els; Concin, Hans; Cooper, Cyrus; Cooper, Rachel; Coppinger, Tara C.; Costanzo, Simona; Cottel, Dominique; Cowell, Chris; Craig, Cora L.; Crujeiras, Ana B.; Cruz, Juan J.; D'Arrigo, Graziella; d'Orsi, Eleonora; Dallongeville, Jean; Damasceno, Albertino; Dankner, Rachel; Dantoft, Thomas M.; Dauchet, Luc; de Backer, Guy; de Gaetano, Giovanni; de Henauw, Stefaan; de Smedt, Delphine; Deepa, Mohan; Dehghan, Abbas; Delisle, Helene; Deschamps, Valerie; Dhana, Klodian; Di Castelnuovo, Augusto F.; Dias-da-Costa, Juvenal Soares; Diaz, Alejandro; Dickerson, Ty T.; Do, Ha T. P.; Dobson, Annette J.; Donfrancesco, Chiara; Donoso, Silvana P.; Doering, Angela; Doua, Kouamelan; Drygas, Wojciech; Dulskiene, Virginija; Dzakula, Aleksandar; Dzerve, Vilnis; Dziankowska-Zaborszczyk, Elzbieta; Eggertsen, Robert; Ekelund, Ulf; El Ati, Jalila; Ellert, Ute; Elosua, Roberto; Erasmus, Rajiv T.; Erem, Cihangir; Eriksen, Louise; Escobedo-de la Pena, Jorge; Evans, Alun; Faeh, David; Fall, Caroline H.; Farzadfar, Farshad; Felix-Redondo, Francisco J.; Ferguson, Trevor S.; Fernandez-Berges, Daniel; Ferrante, Daniel; Ferrari, Marika; Ferreccio, Catterina; Ferrieres, Jean; Finn, Joseph D.; Fischer, Krista; Foeger, Bernhard; Foo, Leng Huat; Forslund, Ann-Sofie; Forsner, Maria; Fortmann, Stephen P.; Fouad, Heba M.; Francis, Damian K.; Franco, Maria do Carmo; Franco, Oscar H.; Frontera, Guillermo; Fuchs, Flavio D.; Fuchs, Sandra C.; Fujita, Yuki; Furusawa, Takuro; Gaciong, Zbigniew; Gareta, Dickman; Garnett, Sarah P.; Gaspoz, Jean-Michel; Gasull, Magda; Gates, Louise; Gavrila, Diana; Geleijnse, Johanna M.; Ghasemian, Anoosheh; Ghimire, Anup; Giampaoli, Simona; Gianfagna, Francesco; Giovannelli, Jonathan; Goldsmith, Rebecca A.; Goncalves, Helen; Gonzalez Gross, Marcela; Gonzalez Rivas, Juan P.; Gottrand, Frederic; Graff-Iversen, Sidsel; Grafnetter, Dusan; Grajda, Aneta; Gregor, Ronald D.; Grodzicki, Tomasz; Grontved, Anders; Gruden, Grabriella; Grujic, Vera; Guan, Ong Peng; Gudnason, Vilmundur; Guerrero, Ramiro; Guessous, Idris; Guimaraes, Andre L.; Gulliford, Martin C.; Gunnlaugsdottir, Johanna; Gunter, Marc; Gupta, Prakash C.; Gureje, Oye; Gurzkowska, Beata; Gutierrez, Laura; Gutzwiller, Felix; Hadaegh, Farzad; Halkjaer, Jytte; Hambleton, Ian R.; Hardy, Rebecca; Harikumar, Rachakulla; Hata, Jun; Hayes, Alison J.; He, Jiang; Hendriks, Marleen Elisabeth; Henriques, Ana; Hernandez Cadena, Leticia; Herqutanto, N. N.; Herrala, Sauli; Heshmat, Ramin; Hihtaniemi, Ilpo Tapani; Ho, Sai Yin; Ho, Suzanne C.; Hobbs, Michael; Hofman, Albert; Dinc, Gonul Horasan; Hormiga, Claudia M.; Horta, Bernardo L.; Houti, Leila; Howitt, Christina; Htay, Thein Thein; Htet, Aung Soe; Hu, Yonghua; Maria Huerta, Jose; Husseini, Abdullatif S.; Huybrechts, Inge; Hwalla, Nahla; Iacoviello, Licia; Iannone, Anna G.; Ibrahim, M. Mohsen; Ikram, M. Arfan; Irazola, Vilma E.; Islam, Muhammad; Ivkovic, Vanja; Iwasaki, Masanori; Jacobs, Jeremy M.; Jafar, Tazeen; Jamrozik, Konrad; Janszky, Imre; Jasienska, Grazyna; Jelakovic, Bojan; Jiang, Chao Qiang; Johansson, Mattias; Jonas, Jost B.; Jorgensen, Torben; Joshi, Pradeep; Juolevi, Anne; Jurak, Gregor; Juresa, Vesna; Kaaks, Rudolf; Kafatos, Anthony; Kalter-Leibovici, Ofra; Kamaruddin, Nor Azmi; Kasaeian, Amir; Katz, Joanne; Kauhanen, Jussi; Kaur, Prabhdeep; Kavousi, Maryam; Kazakbaeva, Gyulli; Keil, Ulrich; Boker, Lital Keinan; Keinanen-Kiukaanniemi, Sirkka; Kelishadi, Roya; Kemper, Han C. G.; Kersting, Mathilde; Key, Timothy; Khader, Yousef Saleh; Khalili, Davood; Khang, Young-Ho; Khaw, Kay-Tee; Kiechl, Stefan; Killewo, Japhet; Kim, Jeongseon; Klumbiene, Jurate; Kolle, Elin; Kolsteren, Patrick; Korrovits, Paul; Koskinen, Seppo; Kouda, Katsuyasu; Koziel, Slawomir; Kristensen, Peter Lund; Krokstad, Steinar; Kromhout, Daan; Kruger, Herculina S.; Kubinova, Ruzena; Kuciene, Renata; Kuh, Diana; Kujala, Urho M.; Kula, Krzysztof; Kulaga, Zbigniew; Kumar, R. Krishna; Kurjata, Pawel; Kusuma, Yadlapalli S.; Kuulasmaa, Kari; Kyobutungi, Catherine; Lachat, Carl; Landrove, Orlando; Lanska, Vera; Lappas, Georg; Larijani, Bagher; Laugsand, Lars E.; Le, Nguyen Bao Khanh; Le, Tuyen D.; Leclercq, Catherine; Lee, Jeannette; Lee, Jeonghee; Lehtimaki, Terho; Lekhraj, Rampal; Leon-Munoz, Luz M.; Levitt, Naomi S.; Li, Yanping; Lilly, Christa L.; Lim, Wei-Yen; Fernanda Lima-Costa, M.; Lin, Hsien-Ho; Lin, Xu; Linneberg, Allan; Lissner, Lauren; Litwin, Mieczyslaw; Lorbeer, Roberto; Lotufo, Paulo A.; Eugenio Lozano, Jose; Luksiene, Dalia; Lundqvist, Annamari; Lunet, Nuno; Lytsy, Per; Ma, Guansheng; Ma, Jun; Machado-Coelho, George L. L.; Machi, Suka; Maggi, Stefania; Magliano, Dianna J.; Majer, Marjeta; Makdisse, Marcia; Malekzadeh, Reza; Malhotra, Rahul; Rao, Kodavanti Mallikharjuna; Malyutina, Sofia; Manios, Yannis; Mann, Jim I.; Manzato, Enzo; Margozzini, Paula; Marques-Vidal, Pedro; Marrugat, Jaume; Martorell, Reynaldo; Mathiesen, Ellisiv B.; Matijasevich, Alicia; Matsha, Tandi E.; Mbanya, Jean Claude N.; Posso, Anselmo J. Mc Donald; McFarlane, Shelly R.; McGarvey, Stephen T.; McLachlan, Stela; McLean, Rachael M.; McNulty, Breige A.; Khir, Amir Sharifuddin Md; Mediene-Benchekor, Sounnia; Medzioniene, Jurate; Meirhaeghe, Aline; Meisinger, Christa; Menezes, Ana Maria B.; Menon, Geetha R.; Meshram, Indrapal I.; Metspalu, Andres; Mi, Jie; Mikkel, Kairit; Miller, Jody C.; Francisco Miquel, Juan; Jaime Miranda, J.; Misigoj-Durakovic, Marjeta; Mohamed, Mostafa K.; Mohammad, Kazem; Mohammadifard, Noushin; Mohan, Viswanathan; Yusoff, Muhammad Fadhli Mohd; Moller, Niels C.; Molnar, Denes; Momenan, Amirabbas; Monyeki, Kotsedi Daniel K.; Moreira, Leila B.; Morejon, Alain; Moreno, Luis A.; Morgan, Karen; Moschonis, George; Mossakowska, Malgorzata; Mostafa, Aya; Mota, Jorge; Motlagh, Mohammad Esmaeel; Motta, Jorge; Muiesan, Maria L.; Mueller-Nurasyid, Martina; Murphy, Neil; Mursu, Jaakko; Musil, Vera; Nagel, Gabriele; Naidu, Balkish M.; Nakamura, Harunobu; Namsna, Jana; Nang, Ei Ei K.; Nangia, Vinay B.; Narake, Sameer; Maria Navarrete-Munoz, Eva; Ndiaye, Ndeye Coumba; Neal, William A.; Nenko, Ilona; Nervi, Flavio; Nguyen, Nguyen D.; Nguyen, Quang Ngoc; Nieto-Martinez, Ramfis E.; Niiranen, Teemu J.; Ning, Guang; Ninomiya, Toshiharu; Nishtar, Sania; Noale, Marianna; Noboa, Oscar A.; Noorbala, Ahmad Ali; Norat, Teresa; Noto, Davide; Al Nsour, Mohannad; O'Reilly, Dermot; Oh, Kyungwon; Olinto, Maria Teresa A.; Oliveira, Isabel O.; Omar, Mohd Azahadi; Onat, Altan; Ordunez, Pedro; Osmond, Clive; Ostojic, Sergej M.; Otero, Johanna A.; Overvad, Kim; Owusu-Dabo, Ellis; Paccaud, Fred Michel; Padez, Cristina; Pahomova, Elena; Pajak, Andrzej; Palli, Domenico; Palmieri, Luigi; Panda-Jonas, Songhomitra; Panza, Francesco; Papandreou, Dimitrios; Parnell, Winsome R.; Parsaeian, Mahboubeh; Pecin, Ivan; Pednekar, Mangesh S.; Peer, Nasheeta; Peeters, Petra H.; Peixoto, Sergio Viana; Pelletier, Catherine; Peltonen, Markku; Pereira, Alexandre C.; Marina Perez, Rosa; Peters, Annette; Petkeviciene, Janina; Pham, Son Thai; Pigeot, Iris; Pikhart, Hynek; Pilav, Aida; Pilotto, Lorenza; Pitakaka, Freda; Plans-Rubio, Pedro; Polakowska, Maria; Polasek, Ozren; Porta, Miquel; Portegies, Marileen L. P.; Pourshams, Akram; Pradeepa, Rajendra; Prashant, Mathur; Price, Jacqueline F.; Puiu, Maria; Punab, Margus; Qasrawi, Radwan F.; Qorbani, Mostafa; Radic, Ivana; Radisauskas, Ricardas; Rahman, Mahfuzar; Raitakari, Olli; Raj, Manu; Rao, Sudha Ramachandra; Ramos, Elisabete; Rampal, Sanjay; Rangel Reina, Daniel A.; Rasmussen, Finn; Redon, Josep; Reganit, Paul Ferdinand M.; Ribeiro, Robespierre; Riboli, Elio; Rigo, Fernando; de Wit, Tobias F. Rinke; Ritti-Dias, Raphael M.; Robinson, Sian M.; Robitaille, Cynthia; Rodriguez-Artalejo, Fernando; Rodriguez-Villamizar, Laura A.; Rojas-Martinez, Rosalba; Rosengren, Annika; Rubinstein, Adolfo; Rui, Ornelas; Sandra Ruiz-Betancourt, Blanca; Russo Horimoto, Andrea R. V.; Rutkowski, Marcin; Sabanayagam, Charumathi; Sachdev, Harshpal S.; Saidi, Olfa; Sakarya, Sibel; Salanave, Benoit; Salazar Martinez, Eduardo; Salmeron, Diego; Salomaa, Veikko; Salonen, Jukka T.; Salvetti, Massimo; Sanchez-Abanto, Jose; Sans, Susana; Santos, Diana; Santos, Ina S.; dos Santos, Renata Nunes; Santos, Rute; Saramies, Jouko L.; Sardinha, Luis B.; Margolis, Giselle Sarganas; Sarrafzadegan, Nizal; Saum, Kai-Uwe; Savva, Savvas C.; Scazufca, Marcia; Schargrodsky, Herman; Schneider, Ione J.; Schultsz, Constance; Schutte, Aletta E.; Sen, Abhijit; Senbanjo, Idowu O.; Sepanlou, Sadaf G.; Sharma, Sanjib K.; Shaw, Jonathan E.; Shibuya, Kenji; Shin, Dong Wook; Shin, Youchan; Siantar, Rosalynn; Sibai, Abla M.; Santos Silva, Diego Augusto; Simon, Mary; Simons, Judith; Simons, Leon A.; Sjotrom, Michael; Skovbjerg, Sine; Slowikowska-Hilczer, Jolanta; Slusarczyk, Przemyslaw; Smith, Margaret C.; Snijder, Marieke B.; So, Hung-Kwan; Sobngwi, Eugene; Soderberg, Stefan; Solfrizzi, Vincenzo; Sonestedt, Emily; Song, Yi; Sorensen, Thorkild I. A.; Jerome, Charles Sossa; Soumare, Aicha; Staessen, Jan A.; Starc, Gregor; Stathopoulou, Maria G.; Stavreski, Bill; Steene-Johannessen, Jostein; Stehle, Peter; Stein, Aryeh D.; Stergiou, George S.; Stessman, Jochanan; Stieber, Jutta; Stoeckl, Doris; Stocks, Tanja; Stokwiszewski, Jakub; Stronks, Karien; Strufaldi, Maria Wany; Sun, Chien-An; Sung, Yn-Tz; Suriyawongpaisal, Paibul; Sy, Rody G.; Tai, E. Shyong; Tammesoo, Mari-Liis; Tamosiunas, Abdonas; Tang, Line; Tang, Xun; Tanser, Frank; Tao, Yong; Tarawneh, Mohammed Rasoul; Tarqui-Mamani, Carolina B.; Taylor, Anne; Theobald, Holger; Thijs, Lutgarde; Thuesen, Betina H.; Tjonneland, Anne; Tolonen, Hanna K.; Topbas, Murat; Topor-Madry, Roman; Jose Tormo, Maria; Torrent, Maties; Traissac, Pierre; Trichopoulos, Dimitrios; Trichopoulou, Antonia; Trinh, Oanh T. H.; Trivedi, Atul; Tshepo, Lechaba; Tulloch-Reid, Marshall K.; Tuomainen, Tomi-Pekka; Turley, Maria L.; Tynelius, Per; Tzourio, Christophe; Ueda, Peter; Ugel, Eunice; Ulmer, Hanno; Uusitalo, Hannu M. T.; Valdivia, Gonzalo; Valvi, Damaskini; van der Schouw, Yvonne T.; van Herck, Koen; van Rossem, Lenie; van Valkengoed, Irene G. M.; Vanderschueren, Dirk; Vanuzzo, Diego; Vatten, Lars; Vega, Tomas; Velasquez-Melendez, Gustavo; Veronesi, Giovanni; Verschuren, W. M. Monique; Verstraeten, Roosmarijn; Victora, Cesar G.; Viet, Lucie; Viikari-Juntura, Eira; Vineis, Paolo; Vioque, Jesus; Virtanen, Jyrki K.; Visvikis-Siest, Sophie; Viswanathan, Bharathi; Vollenweider, Peter; Vrdoljak, Ana; Vrijheid, Martine; Wade, Alisha N.; Wagner, Aline; Walton, Janette; Mohamud, Wan Nazaimoon Wan; Wang, Ming-Dong; Wang, Qian; Wang, Ya Xing; Wannamethee, S. Goya; Wareham, Nicholas; Wederkopp, Niels; Weerasekera, Deepa; Whincup, Peter H.; Widhalm, Kurt; Widyahening, Indah S.; Wiecek, Andrzej; Wijga, Alet H.; Wilks, Rainford J.; Willeit, Peter; Williams, Emmanuel A.; Wilsgaard, Tom; Wojtyniak, Bogdan; Wong, Tien Yin; Wong-McClure, Roy A.; Woo, Jean; Wu, Aleksander Giwercman; Wu, Frederick C.; Wu, Shou Ling; Xu, Haiquan; Yan, Weili; Yang, Xiaoguang; Ye, Xingwang; Yiallouros, Panayiotis K.; Yoshihara, Akihiro; Younger-Coleman, Novie O.; Yusoff, Ahmad F.; Zambon, Sabina; Zdrojewski, Tomasz; Zeng, Yi; Zhao, Dong; Zhao, Wenhua; Zheng, Yingffeng; Zhu, Dan; Zimmermann, Esther; Zuniga Cisneros, Julio

    2017-01-01

    Background Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood

  15. Worldwide trends in blood pressure from 1975 to 2015 : a pooled analysis of 1479 population-based measurement studies with 19·1 million participants

    NARCIS (Netherlands)

    Zhou, B.; Bentham, James; Di Cesare, Mariachiara; Bixby, Honor; Danaei, Goodarz; Cowan, Melanie J.; Paciorek, Christopher J.; Singh, Gitanjali; Hajifathalian, Kaveh; Bennett, James E.; Taddei, Cristina; Bilano, Ver; Carrillo-Larco, Rodrigo M.; Djalalinia, Shirin; Khatibzadeh, Shahab; Lugero, Charles; Peykari, Niloofar; Zhang, Wan Zhu; Lu, Yuan; Stevens, Gretchen A.; Riley, Leanne M.; Bovet, Pascal; Elliott, Paul; Gu, Dongfeng; Ikeda, Nayu; Jackson, Rod T.; Joffres, Michel; Kengne, Andre Pascal; Laatikainen, Tiina; Lam, Tai Hing; Laxmaiah, Avula; Liu, Jing; Miranda, J. Jaime; Mondo, Charles K.; Neuhauser, Hannelore K.; Sundström, Johan; Smeeth, Liam; Sorić, Maroje; Woodward, Mark; Ezzati, Majid; Abarca-Gómez, Leandra; Abdeen, Ziad A.; Rahim, Hanan Abdul; Abu-Rmeileh, Niveen M.; Acosta-Cazares, Benjamin; Adams, Robert; Aekplakorn, Wichai; Afsana, Kaosar; Aguilar-Salinas, Carlos A.; Agyemang, Charles; Ahmadvand, Alireza; Ahrens, Wolfgang; Al Raddadi, Rajaa; Al Woyatan, Rihab; Ali, Mohamed M.; Alkerwi, Ala'a; Aly, Eman; Amouyel, Philippe; Amuzu, Antoinette; Andersen, Lars Bo; Anderssen, Sigmund A.; Ängquist, Lars; Anjana, Ranjit Mohan; Ansong, Daniel; Aounallah-Skhiri, Hajer; Araújo, Joana; Ariansen, Inger; Aris, Tahir; Arlappa, Nimmathota; Aryal, Krishna; Arveiler, Dominique; Assah, Felix K.; Assunção, Maria Cecília F.; Avdicová, Mária; Azevedo, Ana; Azizi, Fereidoun; Babu, Bontha V.; Bahijri, Suhad; Balakrishna, Nagalla; Bandosz, Piotr; Banegas, José R.; Barbagallo, Carlo M.; Barceló, Alberto; Barkat, Amina; Barros, Aluisio J.D.; Barros, Mauro V.; Bata, Iqbal; Batieha, Anwar M.; Baur, Louise A.; Beaglehole, Robert; Romdhane, Habiba Ben; Benet, Mikhail; Benson, Lowell S.; Bernabe-Ortiz, Antonio; Bernotiene, Gailute; Bettiol, Heloisa; Bhagyalaxmi, Aroor; Bharadwaj, Sumit; Bhargava, Santosh K.; Bi, Yufang; Bikbov, Mukharram; Bjerregaard, Peter; Bjertness, Espen; Björkelund, Cecilia; Blokstra, Anneke; Bo, Simona; Bobak, Martin; Boeing, Heiner; Boggia, Jose G.; Boissonnet, Carlos P.; Bongard, Vanina; Braeckman, Lutgart; Brajkovich, Imperia; Branca, Francesco; Breckenkamp, Juergen; Brenner, Hermann; Brewster, Lizzy M.; Bruno, Graziella; Bueno-de-Mesquita, H B As; Bugge, Anna; Burns, Con; Bursztyn, Michael; de León, Antonio Cabrera; Cacciottolo, Joseph; Cameron, Christine; Can, Günay; Cândido, Ana Paula C.; Capuano, Vincenzo; Cardoso, Viviane C.; Carlsson, Axel C.; Carvalho, Maria J.; Casanueva, Felipe F.; Casas, Juan-Pablo; Caserta, Carmelo A.; Chamukuttan, Snehalatha; Chan, Angelique W.; Chan, Queenie; Chaturvedi, Himanshu K.; Chaturvedi, Nishi; Chen, Chien-Jen; Chen, Fangfang; Chen, Huashuai; Chen, Shuohua; Chen, Zhengming; Cheng, Yu Ching; Dekkaki, Imane Cherkaoui; Chetrit, Angela; Chiolero, Arnaud; Chiou, Shu Ti; Chirita-Emandi, Adela; Cho, Belong; Cho, Yumi; Chudek, Jerzy; Cifkova, Renata; Claessens, Frank; Clays, Els; Concin, Hans; Cooper, Cyrus; Cooper, Rachel; Coppinger, Tara C.; Costanzo, Simona; Cottel, Dominique; Cowell, Chris; Craig, Cora L.; Crujeiras, Ana B.; Cruz, Juan J.; D'Arrigo, Graziella; d'Orsi, Eleonora; Dallongeville, Jean; Damasceno, Albertino; Danaei, Goodarz; Dankner, Rachel; Dantoft, Thomas M.; Dauchet, Luc; De Backer, Guy; De Bacquer, Dirk; de Gaetano, Giovanni; De Henauw, Stefaan; De Smedt, Delphine; Deepa, Mohan; Dehghan, Abbas; Delisle, Hélène; Deschamps, Valérie; Dhana, Klodian; Di Castelnuovo, Augusto F.; Dias-da-Costa, Juvenal Soares; Diaz, Alejandro; Dickerson, Ty T.; Do, Ha T.P.; Dobson, Annette J.; Donfrancesco, Chiara; Donoso, Silvana P.; Döring, Angela; Doua, Kouamelan; Drygas, Wojciech; Dulskiene, Virginija; Džakula, Aleksandar; Dzerve, Vilnis; Dziankowska-Zaborszczyk, Elzbieta; Eggertsen, Robert; Ekelund, Ulf; El Ati, Jalila; Ellert, Ute; Elliott, Paul; Elosua, Roberto; Erasmus, Rajiv T.; Erem, Cihangir; Eriksen, Louise; Escobedo-de la Peña, Jorge; Evans, Alun; Faeh, David; Fall, Caroline H.; Farzadfar, Farshad; Felix-Redondo, Francisco J.; Ferguson, Trevor S.; Fernández-Bergés, Daniel; Ferrante, Daniel; Ferrari, Marika; Ferreccio, Catterina; Ferrieres, Jean; Finn, Joseph D.; Fischer, Krista; Föger, Bernhard; Foo, Leng Huat; Forslund, Ann Sofie; Forsner, Maria; Fortmann, Stephen P.; Fouad, Heba M.; Francis, Damian K.; do Carmo Franco, Maria; Franco, Oscar H.; Frontera, Guillermo; Fuchs, Flavio D.; Fuchs, Sandra C.; Fujita, Yuki; Furusawa, Takuro; Gaciong, Zbigniew; Gareta, Dickman; Garnett, Sarah P.; Gaspoz, Jean-Michel; Gasull, Magda; Gates, Louise; Gavrila, Diana; Geleijnse, Johanna M.; Ghasemian, Anoosheh; Ghimire, Anup; Giampaoli, Simona; Gianfagna, Francesco; Giovannelli, Jonathan; Goldsmith, Rebecca A.; Gonçalves, Helen; Gross, Marcela Gonzalez; González Rivas, Juan P.; Gottrand, Frederic; Graff-Iversen, Sidsel; Grafnetter, Dušan; Grajda, Aneta; Gregor, Ronald D.; Grodzicki, Tomasz; Grøntved, Anders; Gruden, Grabriella; Grujic, Vera; Gu, Dongfeng; Guan, Ong Peng; Gudnason, Vilmundur; Guerrero, Ramiro; Guessous, Idris; Guimaraes, Andre L.; Gulliford, Martin C.; Gunnlaugsdottir, Johanna; Gunter, Marc J.; Gupta, Prakash C.; Gureje, Oye; Gurzkowska, Beata; Gutierrez, Laura; Gutzwiller, Felix; Hadaegh, Farzad; Halkjær, Jytte; Hambleton, Ian R.; Hardy, Rebecca; Harikumar, Rachakulla; Hata, Jun; Hayes, Alison J.; He, Jiang; Hendriks, Marleen Elisabeth; Henriques, Ana; Cadena, Leticia Hernandez; Herrala, Sauli; Heshmat, Ramin; Hihtaniemi, Ilpo Tapani; Ho, Sai Yin; Ho, Suzanne C.; Hobbs, Michael; Hofman, Albert; Dinc, Gonul Horasan; Hormiga, Claudia M.; Horta, Bernardo Lessa; Houti, Leila; Howitt, Christina; Htay, Thein Thein; Htet, Aung Soe; Hu, Yonghua; Huerta, José María; Husseini, Abdullatif S.; Huybrechts, Inge; Hwalla, Nahla; Iacoviello, Licia; Iannone, Anna G.; Ibrahim, M. Mohsen; Ikram, M. Arfan; Irazola, Vilma E.; Islam, Muhammad; Ivkovic, Vanja; Iwasaki, Masanori; Jackson, Rod T.; Jacobs, Jeremy M.; Jafar, Tazeen; Jamrozik, Konrad; Janszky, Imre; Jasienska, Grazyna; Jelakovic, Bojan; Jiang, Chao Qiang; Joffres, Michel; Johansson, Mattias; Jonas, Jost B; Jørgensen, Torben; Joshi, Pradeep; Juolevi, Anne; Jurak, Gregor; Jureša, Vesna; Kaaks, Rudolf; Kafatos, Anthony; Kalter-Leibovici, Ofra; Kamaruddin, Nor Azmi; Kasaeian, Amir; Katz, Joanne; Kauhanen, Jussi; Kaur, Prabhdeep; Kavousi, Maryam; Kazakbaeva, Gyulli; Keil, Ulrich; Boker, Lital Keinan; Keinänen-Kiukaanniemi, Sirkka; Kelishadi, Roya; Kemper, Han C.G.; Kengne, Andre Pascal; Kersting, Mathilde; Key, Timothy J.; Khader, Yousef Saleh; Khalili, Davood; Khang, Young Ho; Khaw, Kay Tee; Kiechl, Stefan; Killewo, Japhet; Kim, Jeongseon; Klumbiene, Jurate; Kolle, Elin; Kolsteren, Patrick; Korrovits, Paul; Koskinen, Seppo; Kouda, Katsuyasu; Koziel, Slawomir; Kristensen, Peter Lund; Krokstad, Steinar; Kromhout, Daan; Kruger, Herculina S.; Kubinova, Ruzena; Kuciene, Renata; Kuh, Diana; Kujala, Urho M.; Kula, Krzysztof; Kulaga, Zbigniew; Krishna Kumar, R.; Kurjata, Pawel; Kusuma, Yadlapalli S.; Kuulasmaa, Kari; Kyobutungi, Catherine; Laatikainen, Tiina; Lachat, Carl; Lam, Tai Hing; Landrove, Orlando; Lanska, Vera; Lappas, Georg; Larijani, Bagher; Laugsand, Lars E.; Laxmaiah, Avula; Le Nguyen Bao, Khanh; Le, Tuyen D.; Leclercq, Catherine; Lee, Jeannette; Lee, Jeonghee; Lehtimäki, Terho; Lekhraj, Rampal; León-Muñoz, Luz M.; Levitt, Naomi S.; Li, Yanping; Lilly, Christa L.; Lim, Wei-Yen; Lima-Costa, M. Fernanda; Lin, Hsien Ho; Lin, Xu; Linneberg, Allan; Lissner, Lauren; Litwin, Mieczyslaw; Lorbeer, Roberto; Lotufo, Paulo A.; Lozano, José Eugenio; Luksiene, Dalia; Lundqvist, Annamari; Lunet, Nuno; Lytsy, Per; Ma, Guansheng; Ma, Jun; Machado-Coelho, George L.L.; Machi, Suka; Maggi, Stefania; Magliano, Dianna J.; Majer, Marjeta; Makdisse, Marcia; Malekzadeh, Reza; Malhotra, Rahul; Rao, Kodavanti Mallikharjuna; Malyutina, Sofia; Manios, Yannis; Mann, Jim I.; Manzato, Enzo; Margozzini, Paula; Marques-Vidal, Pedro; Marrugat, Jaume; Martorell, Reynaldo; Mathiesen, Ellisiv B.; Matijasevich, Alicia; Matsha, Tandi E.; Mbanya, Jean Claude N.; McDonald Posso, Anselmo J.; McFarlane, Shelly R.; McGarvey, Stephen T.; McLachlan, Stela; McLean, Rachael M.; McNulty, Breige A.; MdKhir, Amir Sharifuddin; Mediene-Benchekor, Sounnia; Medzioniene, Jurate; Meirhaeghe, Aline; Meisinger, Christa; Menezes, Ana Maria B.; Menon, Geetha R.; Meshram, Indrapal I.; Metspalu, Andres; Mi, Jie; Mikkel, Kairit; Miller, Jody C.; Miquel, Juan-Francisco; Mišigoj-Durakovic, Marjeta; Mohamed, Mostafa K.; Mohammad, Kazem; Mohammadifard, Noushin; Mohan, Viswanathan; Mohd Yusoff, Muhammad Fadhli; Møller, Niels C.; Molnár, Dénes; Momenan, Amirabbas; Mondo, Charles K.; Monyeki, Kotsedi Daniel K.; Moreira, Leila B.; Morejon, Alain; Moreno, Luis A.; Morgan, Karen; Moschonis, George; Mossakowska, Malgorzata; Mota, Jorge; Mostafa, Aya; Motlagh, Mohammad Esmaeel; Motta, Jorge; Muiesan, Maria L.; Müller-Nurasyid, Martina; Murphy, Neil; Mursu, Jaakko; Musil, Vera; Nagel, Gabriele; Naidu, Balkish M.; Nakamura, Harunobu; Námešná, Jana; Nang, Ei Ei K.; Nangia, Vinay B.; Narake, Sameer; Navarrete-Muñoz, Eva Maria; Ndiaye, Ndeye Coumba; Neal, William A.; Nenko, Ilona; Nervi, Flavio; Nguyen, Nguyen D.; Nguyen, Quang Ngoc; Nieto-Martínez, Ramfis E.; Niiranen, Teemu J.; Ning, Guang; Ninomiya, Toshiharu; Nishtar, Sania; Noale, Marianna; Noboa, Oscar A.; Noorbala, Ahmad Ali; Norat, Teresa; Noto, Davide; Al Nsour, Mohannad; O'Reilly, Dermot; Oh, Kyungwon; Olinto, Maria Teresa A.; Oliveira, Isabel O.; Omar, Mohd Azahadi; Onat, Altan; Ordunez, Pedro; Osmond, Clive; Ostojic, Sergej M.; Otero, Johanna A.; Overvad, Kim; Owusu-Dabo, Ellis; Paccaud, Fred Michel; Padez, Cristina; Pahomova, Elena; Pajak, Andrzej; Palli, Domenico; Palmieri, Luigi; Panda-Jonas, Songhomitra; Panza, Francesco; Papandreou, Dimitrios; Parnell, Winsome R.; Parsaeian, Mahboubeh; Pecin, Ivan; Pednekar, Mangesh S.; Peer, Nasheeta; Peeters, Petra H.; Peixoto, Sergio Viana; Pelletier, Catherine; Peltonen, Markku; Pereira, Alexandre C.; Pérez, Rosa Marina; Peters, Annette; Petkeviciene, Janina; Pham, Son Thai; Pigeot, Iris; Pikhart, Hynek; Pilav, Aida; Pilotto, Lorenza; Pitakaka, Freda; Plans-Rubió, Pedro; Polakowska, Maria; Polašek, Ozren; Porta, Miquel; Portegies, Marileen L.P.; Pourshams, Akram; Pradeepa, Rajendra; Prashant, Mathur; Price, Jacqueline F.; Puiu, Maria; Punab, Margus; Qasrawi, Radwan F.; Qorbani, Mostafa; Radic, Ivana; Radisauskas, Ricardas; Rahman, Mahfuzar; Raitakari, Olli T.; Raj, Manu; Rao, Sudha Ramachandra; Ramachandran, Ambady; Ramos, Elisabete; Rampal, Sanjay; Rangel Reina, Daniel A.; Rasmussen, Finn; Redon, Josep; Reganit, Paul Ferdinand M.; Ribeiro, Robespierre; Riboli, Elio; Rigo, Fernando; Rinke de Wit, Tobias F.; Ritti-Dias, Raphael M.; Robinson, Sian M.; Robitaille, Cynthia; Rodríguez-Artalejo, Fernando; del Cristo Rodriguez-Perez, María; Rodríguez-Villamizar, Laura A.; Rojas-Martinez, Rosalba; Rosengren, Annika; Rubinstein, Adolfo; Rui, Ornelas; Ruiz-Betancourt, Blanca Sandra; Russo Horimoto, Andrea R.V.; Rutkowski, Marcin; Sabanayagam, Charumathi; Sachdev, Harshpal S.; Saidi, Olfa; Sakarya, Sibel; Salanave, Benoit; Martinez, Eduardo Salazar; Salmerón, Diego; Salomaa, Veikko; Salonen, Jukka T.; Salvetti, Massimo; Sánchez-Abanto, Jose; Sans, Susana; Santos, Diana; Santos, Ina S.; dos Santos, Renata Nunes; Santos, Rute; Saramies, Jouko L.; Sardinha, Luis B.; Margolis, Giselle Sarganas; Sarrafzadegan, Nizal; Saum, Kai Uwe; Savva, Savvas C.; Scazufca, Marcia; Schargrodsky, Herman; Schneider, Ione J.; Schultsz, Constance; Schutte, Aletta E.; Schutte, Aletta E.; Sen, Abhijit; Senbanjo, Idowu O.; Sepanlou, Sadaf G.; Sharma, Sanjib K.; Shaw, Jonathan E.; Shibuya, Kenji; Shin, Dong Wook; Shin, Youchan; Siantar, Rosalynn; Sibai, Abla M.; Santos Silva, Diego Augusto; Simon, Mary; Simons, Judith; Simons, Leon A; Sjöström, Michael; Skovbjerg, Sine; Slowikowska-Hilczer, Jolanta; Slusarczyk, Przemyslaw; Smith, Margaret C.; Snijder, Marieke B.; So, Hung Kwan; Sobngwi, Eugène; Söderberg, Stefan; Solfrizzi, Vincenzo; Sonestedt, Emily; Song, Yi; Sørensen, Thorkild I A; Soric, Maroje; Jérome, Charles Sossa; Soumare, Aicha; Staessen, Jan A.; Starc, Gregor; Stathopoulou, Maria G.; Stavreski, Bill; Steene-Johannessen, Jostein; Stehle, Peter; Stein, Aryeh D.; Stergiou, George S.; Stessman, Jochanan; Stieber, Jutta; Stöckl, Doris; Stocks, Tanja; Stokwiszewski, Jakub; Stronks, Karien; Strufaldi, Maria Wany; Sun, Chien An; Sung, Yn Tz; Suriyawongpaisal, Paibul; Sy, Rody G.; Tai, E. Shyong; Tammesoo, Mari Liis; Tamosiunas, Abdonas; Tang, Line; Tang, Xun; Tao, Yong; Tanser, Frank; Tarawneh, Mohammed Rasoul; Tarqui-Mamani, Carolina B.; Taylor, Anne; Theobald, Holger; Thijs, Lutgarde; Thuesen, Betina Heinsbek; Tjonneland, Anne; Tolonen, Hanna K.; Tolstrup, Janne S.; Topbas, Murat; Topór-Madry, Roman; Tormo, María José; Torrent, Maties; Traissac, Pierre; Trichopoulos, Dimitrios; Trichopoulou, Antonia; Trinh, Oanh T.H.; Trivedi, Atul; Tshepo, Lechaba; Tulloch-Reid, Marshall K.; Tuomainen, Tomi-Pekka; Tuomilehto, Jaakko; Turley, Maria L.; Tynelius, Per; Tzourio, Christophe; Ueda, Peter; Ugel, Eunice; Ulmer, Hanno; Uusitalo, Hannu M.T.; Valdivia, Gonzalo; Valvi, Damaskini; van der Schouw, Yvonne T.; Van Herck, Koen; van Rossem, Lenie; Van Valkengoed, Irene G M; Vanderschueren, Dirk; Vanuzzo, Diego; Vatten, Lars; Vega, Tomas; Velasquez-Melendez, Gustavo; Veronesi, Giovanni; Verschuren, W. M.Monique; Verstraeten, Roosmarijn; Victora, Cesar G.; Viet, Lucie; Viikari-Juntura, Eira; Vineis, Paolo; Vioque, Jesus; Virtanen, Jyrki K.; Visvikis-Siest, Sophie; Viswanathan, Bharathi; Vollenweider, Peter; Voutilainen, Sari; Vrdoljak, Ana; Vrijheid, Martine; Wade, Alisha N.; Wagner, Aline; Walton, Janette; Wan Mohamud, Wan Nazaimoon; Wang, Ming Dong; Wang, Qian; Wang, Ya Xing; Wannamethee, S. Goya; Wareham, Nicholas J.; Wederkopp, Niels; Weerasekera, Deepa; Whincup, Peter H.; Widhalm, Kurt; Widyahening, Indah S.; Wijga, Alet H; Wiecek, Andrzej; Wilks, Rainford J.; Willeit, Johann; Willeit, Peter; Williams, Emmanuel A.; Wilsgaard, Tom; Wojtyniak, Bogdan; Wong, Tien-Yin; Wong-McClure, Roy A.; Woo, Jean; Woodward, Mark; Woodward, Mark; Wu, Aleksander Giwercman; Wu, Frederick C.; Wu, Shou Ling; Xu, Haiquan; Yan, Weili; Yang, Xiaoguang; Ye, Xingwang; Yiallouros, Panayiotis K.; Yoshihara, Akihiro; Younger-Coleman, Novie O.; Yusoff, Ahmad F.; Yusoff, Muhammad Fadhli M.; Zambon, Sabina; Zdrojewski, Tomasz; Zeng, Yi-Xin; Zeng, Yi-Xin; Zhao, Dong; Zhao, Wenhua; Zheng, Yingffeng; Zimmermann, Esther; Cisneros, Julio Zuñiga; Zhu, Dan

    2017-01-01

    Background Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood

  16. Worldwide trends in blood pressure from 1975 to 2015 : a pooled analysis of 1479 population-based measurement studies with 19.1 million participants

    NARCIS (Netherlands)

    Zhou, Bin; Bentham, James; Di Cesare, Mariachiara; Bixby, Honor; Danaei, Goodarz; Cowan, Melanie J.; Paciorek, Christopher J.; Singh, Gitanjali M; Hajifathalian, Kaveh; Bennett, James E.; Taddei, Cristina; Bilano, Ver; Carrillo-Larco, Rodrigo M.; Djalalinia, Shirin; Khatibzadeh, Shahab; Lugero, Charles; Peykari, Niloofar; Zhang, Wan Zhu; Lu, Yuan; Stevens, Gretchen A.; Riley, Leanne M.; Bovet, Pascal; Elliott, Paul; Gu, Dongfeng; Ikeda, Nayu; Jackson, Rod T.; Joffres, Michel; Kengne, Andre-Pascal; Laatikainen, Tiina; Lam, Tai Hing; Laxmaiah, Avula; Liu, Jing; Miranda, J. Jaime; Mondo, Charles K.; Neuhauser, Hannelore K.; Sundstrom, Johan; Smeeth, Liam; Soric, Maroje; Woodward, Mark; Ezzati, Majid; Abarca-Gomez, Leandra; Abdeen, Ziad A.; Rahim, Hanan Abdul; Abu-Rmeileh, Niveen Me; Acosta-Cazares, Benjamin; Adams, Robert; Aekplakorn, Wichai; Afsana, Kaosar; Aguilar-Salinas, Carlos A; Kromhout, Daan

    2017-01-01

    Background Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood

  17. Hawaii ESI: POOLS (Anchialine Pool Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

  18. Defective mitochondrial respiration, altered dNTP pools and reduced AP endonuclease 1 activity in peripheral blood mononuclear cells of Alzheimer's disease patients

    DEFF Research Database (Denmark)

    Maynard, Scott; Hejl, Anne-Mette; Dinh, Tran Thuan Son

    2015-01-01

    AIMS: Accurate biomarkers for early diagnosis of Alzheimer's disease (AD) are badly needed. Recent reports suggest that dysfunctional mitochondria and DNA damage are associated with AD development. In this report, we measured various cellular parameters, related to mitochondrial bioenergetics...... as possible. We measured glycolysis and mitochondrial respiration fluxes using the Seahorse Bioscience flux analyzer, mitochondrial ROS production using flow cytometry, dNTP levels by way of a DNA polymerization assay, DNA strand breaks using the Fluorometric detection of Alkaline DNA Unwinding (FADU) assay...... on adjustments for gender and/or age. CONCLUSIONS: This study reveals impaired mitochondrial respiration, altered dNTP pools and reduced DNA repair activity in PBMCs of AD patients, thus suggesting that these biochemical activities may be useful as biomarkers for AD....

  19. Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases; Evaluation with gated blood pool scintigraphy using [sup 99m]Tc

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Tomiro (Okayama Univ. (Japan). School of Medicine)

    1993-06-01

    Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author).

  20. Blood pressure and fasting lipid changes after 24 weeks' treatment with vildagliptin: a pooled analysis in >2,000 previously drug-naïve patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Evans, Marc; Schweizer, Anja; Foley, James E

    2016-01-01

    We have previously shown modest weight loss with vildagliptin treatment. Since body weight balance is associated with changes in blood pressure (BP) and fasting lipids, we have assessed these parameters following vildagliptin treatment. Data were pooled from all double-blind, randomized, controlled, vildagliptin mono-therapy trials on previously drug-naïve patients with type 2 diabetes mellitus who received vildagliptin 50 mg once daily (qd) or twice daily (bid; n=2,108) and wherein BP and fasting lipid data were obtained. Data from patients receiving vildagliptin 50 mg qd or bid showed reductions from baseline to week 24 in systolic BP (from 132.5±0.32 to 129.8±0.34 mmHg; Pvildagliptin shows a significant reduction in BP and a favorable fasting lipid profile that are associated with modest weight loss.

  1. Blood

    Science.gov (United States)

    ... a reduced production of red blood cells, including: Iron deficiency anemia. Iron deficiency anemia is the most common type of anemia and ... inflammatory bowel disease are especially likely to have iron deficiency anemia. Anemia due to chronic disease. People with chronic ...

  2. Assessment of left ventricular function by electrocardiogram-gated myocardial single photon emission computed tomography using quantitative gated single photon emission computed tomography software

    International Nuclear Information System (INIS)

    Morita, Koichi; Adachi, Itaru; Konno, Masanori

    1999-01-01

    Electrocardiogram (ECG)-gated myocardial single photon emission computed tomography (SPECT) can assess left ventricular (LV) perfusion and function easily using quantitative gated SPECT (QGS) software. ECG-gated SPECT was performed in 44 patients with coronary artery disease under post-stress and resting conditions to assess the values of LV functional parameters, by comparison to LV ejection fraction derived from gated blood pool scan and myocardial characteristics. A good correlation was obtained between ejection fraction using QGS and that using cardiac blood pool scan (r=0.812). Some patients with myocardial ischemia had lower ejection fraction under post-stress compared to resting conditions, indicating post-stress LV dysfunction. LV wall motion and wall thickening were significantly impaired in ischemic and infarcted myocardium, and the degree of abnormality in the infarcted areas was greater than in the ischemia area. LV functional parameters derived using QGS were useful to assess post-stress LV dysfunction and myocardial viability. In conclusion, ECG-gated myocardial SPECT permits simultaneous quantitative assessment of myocardial perfusion and function. (author)

  3. Fourier analysis of multi-gated cardiac blood-pool data in patients with congenital heart diseases, (2). Assessment of diseases with complex cardiac anomalies, especially tetralogy of Fallot

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kan; Maeda, Hisato; Yamaguchi, Nobuo; Nakamura, Kazuyoshi; Matsumura, Kaname; Nakagawa, Tsuyoshi; Sakurai, Minoru; Aoki, Kenzo

    1985-04-01

    The clinical usefulness of Fourier analysis of multi-gated cardiac blood-pool data was evaluated in 18 subjects with normal cardiac functions and 14 patients with complex cardiac anomalies (ten with tetralogy of Fallot, two with tricuspid atresia (TA), one with double-outlet right ventricle (DORV), and one with Ebstein's anomaly (EA)). Using global ventricular time-activity curves, the phase and amplitude at fundamental frequency were calculated, and emptying patterns of the left and right ventricles (LV, RV) were evaluated by phase difference (D(phase)=RV phase minus LV phase) and amplitude ratio of RV to LV (R(amp)). In patients with TOF, mean values of D (phase) and R(amp) were 25.3 +- 10.5 degrees and 13.5 +- 0.49 respectively and significantly larger than those of normal subjects. D (phase) became larger in inverse proportion to the ratio of pulmonary-to-systemic blood flow and there was an inverse linear correlation between these two variables. On visual interpretation of functional images, the dynamic property of hypoplastic ventricles could be easily estimated in patients with TA or DORV. In a case with EA, the atrialized RV was shown clearly as a hypokinetic, atrial phase area. This method is valuable for pathophysiologic investigation of diseases with complex cardiac anomalies. (author).

  4. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  5. Swimming pool granuloma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

  6. Reproducibility of GBPI - gated blood-pool imaging in LVEF - left ventricle ejection fraction assessment in patients with big infarcts and a control group

    International Nuclear Information System (INIS)

    Guevara, David Ladron de; Lobo, Gabriel; Perez, Andres; Jimenez, Cesar; Wolff, Carlos

    2003-01-01

    GBPI allows to study global and regional myocardial contractility, calculating LVEF accurately and easily. Intra and inter observer reproducibility of these measurements depends of clinical group studied, acquisition parameters, gamma camera and software used, and operator. The aim of this study was to evaluate the LVEF assessment reproducibility in patients with big infarcts and a control group, using two different gamma cameras. Material and method. GBPI of 13 patients with large infarcts and 12 healthy young control individuals were done, using sequentially both gamma camera Picker 37/15 and SMV DST Xli, with exactly the same acquisition parameters in both. Each individual was injected once with 925 MBq (25 mCi) of in vitro labelled Tc 99 m red blood cells. Ten LVEF measurements by patient were done, calculating the variability coefficient (VC) of these values for each clinical group in both gamma cameras for comparison. Correlation and Bland-Altman analysis of LVEF values were performed. Results. Infarcted patients had higher values of VC than controls (3.5% vs 2.3% in Picker, 3.5% vs 2.1% in SMV DST XLi). Variability of LVEF measurements of both gamma cameras was almost identical. Picker equipment yielded LVEF values slightly higher than SMV DST XLi equipment, especially in infarcted patients. However, a strong correlation between both gamma cameras was found (r:0.97).Conclusion. Reproducibility of both gamma cameras is almost identical, very high, and significantly higher in control individuals than infarcted patients. (author)

  7. The effects of nisoldipine on left ventricular filling rate in patients with ischemic heart disease measured with radionuclide gated blood pool scintigraphy

    International Nuclear Information System (INIS)

    Otto, A.C.; Viviers, A.C.

    1988-01-01

    Nisoldipine is a newly developed calcium channel blocker with outstanding vasodilatory properties especially with regard to the coronary arteries. Thus it may find wide-spread application as a therapeutic agent in various ischemic heart disease syndromes. The purpose of this study was to evaluate the effect of nisoldipine on the diastolic function of the left ventricle (LV) in the clinical situation. A patient group on nisoldipine treatment was compared to a control group. In the nisoldipine group a maximum decrease of 17 mmHg in the mean systolic blood pressure with an increase in the mean peak ejection rate (0.78 EDV/s) and peak filling rate (0.52 EDV/s) were observed. Mean LV ejection fraction increased by 6.4% and the time to peak filling rate decreased by 36.5 ms. After eight weeks of treatment the acute effects of nisoldipine were similar to the previous study. Nisoldipine therefore tends to improve both the diastolic and systolic function of the left ventricle. (orig.)

  8. A study evaluating of the dependence of the clinical usefulness on the use of a half-time acquisition factor in a multiple-gated blood-pool (MUGA) scan using Tc-99 m

    Science.gov (United States)

    Lee, Dong-Hun; Jung, Woo-Young; Kim, Ho-Sung; Dong, Kyung-Rae; Park, Yong-Soon; Chung, Woon-Kwan; Cho, Jae-Hwan; Yeo, Hwa-Yeon

    2012-12-01

    This study evaluated the clinical usefulness of reducing the scan time based on a comparative analysis of the left ventricular cardiac ejection fraction of a full-time image in a gated cardiac blood-pool scan by using the half-time image obtained by applying an image processing technique and using the results from a blind test conducted by radiologists. Fifty patients who underwent a multiple-gated blood-pool (MUGA) scan at the Nuclear Medicine Department of ASAN Medical Center from June 20 to August 14, 2011 were enrolled in this study. Images of the left anterior oblique (LAO) view were obtained continuously in full time (6,000 kcts) and half time (3,000 kcts) in the same posture. The obtained images were used to calculate the left ventricular cardiac ejection fraction 10 times in the full-time image, the half-time image obtained without applying an image processing technique, and the half-time image obtained by applying an image processing technique. To evaluate the cardiac ejection fraction under the same conditions, we set the regions of interest (ROIs) of the left ventricle and the background radioactivity to be the automated ROIs on the same X and Y axes. According to the results of quantitative analyses of the cardiac ejection fraction, the mean ± standard deviation value for the full-time image, the half-time image obtained without applying an image processing technique, and the half-time images obtained by applying an image processing technique were 69.1 ± 7.6%, 68.2 ± 8.4%, and 68.7 ± 8.0%, respectively. The cardiac ejection fraction did not show any significant difference (p > 0.05). For a qualitative analysis, a blinding test was conducted with two radiologists. According to the test results, when the examination was conducted for cardiac wall motion of the left ventricle, no difference was found between the full-time and half-time images obtained by applying an image processing technique.

  9. Extremely Small Pseudoparamagnetic Iron Oxide Nanoparticle as a Novel Blood Pool T1 Magnetic Resonance Contrast Agent for 3 T Whole-Heart Coronary Angiography in Canines: Comparison With Gadoterate Meglumine.

    Science.gov (United States)

    Park, Eun-Ah; Lee, Whal; So, Young Ho; Lee, Yun-Sang; Jeon, Bong-Sik; Choi, Kyu Sung; Kim, Eung-Gyu; Myeong, Wan-Jae

    2017-02-01

    The aim of this study was to evaluate an extremely small pseudoparamagnetic iron oxide nanoparticle (ESPIO), KEG3, as a potential blood pool agent in 3 T coronary magnetic resonance angiography (MRA) in canine models and compare its efficacy to that of a gadolinium-based contrast agent. Nine mongrel dogs were subjected to whole-heart coronary MRA in 2 separate sessions at 7-day intervals with a 3 T scanner using the FLASH sequence with either gadoterate meglumine (Gd-DOTA) or the ESPIO (KEG3). Coronary MRA was performed twice at each MR examination: the first scan during the administration of the contrast agent and the subsequent second scan at 15 minutes after contrast injection. Objective measurements of the Gd-DOTA and ESPIO images, including the signal-to-noise ratios (SNRs) for the coronary arteries and cardiac veins, contrast-to-noise ratios (CNRs) between the vessels and fat (CNRfat) and the vessels and the myocardium (CNRmyocardium), and subjective image quality scores on a 4-point scale were evaluated and compared. The mean SNRs and CNRs of all vascular regions in the ESPIO images were similar to those of the corresponding regions in the Gd-DOTA images in the first scan (98.1 ± 32.5 vs 79.1 ± 38.4 for SNR of coronary arteries, P = 0.3; 74.2 ± 30.1 vs 61.4 ± 38.5 for CNR, P = 0.7) and more than 2 times higher than the latter in the second scan (95.2 ± 31.3 vs 32.1 ± 8.1 for SNR of coronary arteries, P = 0.008; 76.1 ± 35.8 vs 17.6 ± 19.2 for CNR, P 0.008). Similarly, the mean values of the subjective measurements of the ESPIO images were similar to those of the Gd-DOTA images (3.9 ± 0.3 vs 3.3 ± 0.8 for coronary arteries, P = 0.1) in the first scan and significantly better than the latter in the second scan (3.9 ± 0.2 vs 2.1 ± 0.6 for coronary arteries, P = 0.007). The experimental blood pool agent KEG3 offers equivalent image quality for whole-heart coronary MRA at 3 T upon contrast administration and persistent better quality in the subsequent

  10. Solar swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

  11. Hierarchical Modeling of Patient and Physician Determinants of Blood Pressure Outcomes in Hypertensive Patients with and without Diabetes: Pooled Analysis of Six Observational Valsartan Studies with 15,282 Evaluable Patients

    Directory of Open Access Journals (Sweden)

    Noha Ashy

    2017-01-01

    Full Text Available We pooled data from 6 valsartan-related studies including 3,658 diabetic and 11,624 nondiabetic patients to evaluate blood pressure (BP outcomes after approximately 90 days of second- or later-line valsartan treatment. Hierarchical linear and logistic regressions were applied to identify determinants of BP outcomes. Similar reductions in BP values and similar BP control rates were achieved in both groups after approximately 90 days of therapy. The modeling analyses identified several common and different patient- and physician-related determinants of BP outcomes for both groups, many of which are modifiable or clinically manageable. Through varying in terms of association and influence between the diabetic and nondiabetic groups, patient-related determinants included age, BP at diagnosis of hypertension, risk factors, valsartan regimen, concomitant antihypertensive treatment, and adherence; and physician-related determinants included gender, years in practice, and hypertension management. In summary, in both diabetic and nondiabetic patients, the use of valsartan-centric treatment regimens in second- or later-line antihypertensive treatment is associated with significant reductions in BP level and improvement in BP control. The determinants identified in modeling provide guidance to clinicians in the common and differential management of hypertension in diabetic and nondiabetic patients.

  12. A pooled analysis of on-the-road highway driving studies in actual traffic measuring standard deviation of lateral position (i.e., "weaving") while driving at a blood alcohol concentration of 0.5 g/L.

    Science.gov (United States)

    Jongen, S; Vermeeren, A; van der Sluiszen, N N J J M; Schumacher, M B; Theunissen, E L; Kuypers, K P C; Vuurman, E F P M; Ramaekers, J G

    2017-03-01

    The on-the-road highway driving test is generally regarded as a gold standard for assessing drug-induced driving impairment. The primary outcome measure is the standard deviation of lateral position (SDLP), a measure of road tracking error or "weaving". The test has been calibrated for incremental doses of alcohol almost 30 years ago in order to define the impact of drug-induced impairment in terms of blood alcohol concentration (BAC) equivalents. Drug-induced changes in SDLP exceeding 2.4 cm have been evaluated as clinically relevant ever since. The present analysis was conducted to assess the robustness of the alcohol effect in a range of on-the-road driving studies which have been conducted since the initial alcohol calibration study. The present study pooled data of 182 participants from nine placebo-controlled crossover studies who performed the highway driving test, while their BAC was at or just below the legal limit for drivers (i.e., 0.5 g/L). Overall, mean SDLP increased with 2.5 cm (95% CI 2.0-2.9 cm). Equivalence testing showed that the clinical relevance criterion value of 2.4 cm fell well within the 95% CI in each individual study. Gender did not affect alcohol-induced changes in SDLP. These results demonstrate the robustness and validity of the clinical relevance criterion for SDLP as measured during on-the-road driving.

  13. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  14. Oncogenic osteomalacia diagnosed by blood pool scintigraphy

    International Nuclear Information System (INIS)

    Palaniswamy, Shanmuga Sundaram; Subramanyam, Padma; Kumar, Harish

    2011-01-01

    Oncogenic osteomalacia is a rare metabolic bone disease characterized by phosphaturia and hypophosphatemia. Certain tumors secrete a phosphaturic factor, which results in this metabolic abnormality; this factor called as phosphatonin, is in fact a fibroblast growth factor 23 (FGF-23) involved closely in phosphate homeostasis and skeletogenesis. Complete excision of these tumors facilitates reversal of the problem. We have reported here the case of a patient who was crippled with this disease and on thorough investigation revealed an oncogenic osteomalacia with tumor focus in the right tibia. The tumor was identified as a mesenchymal tumor, i.e., hemangiopericytoma. Tumor excision alleviated patient symptoms with rapid symptomatic and biochemical improvement

  15. Blood pressure and fasting lipid changes after 24 weeks’ treatment with vildagliptin: a pooled analysis in >2,000 previously drug-naïve patients with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Evans M

    2016-08-01

    Full Text Available Marc Evans,1 Anja Schweizer,2 James E Foley3 1Diabetes Resource Centre, Llandough Hospital, Cardiff, UK; 2Medical Affairs Cardio Metabolic, Novartis Pharma AG, Basel, Switzerland; 3Medical Affairs Cardio-Metabolic, Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA Introduction: We have previously shown modest weight loss with vildagliptin treatment. Since body weight balance is associated with changes in blood pressure (BP and fasting lipids, we have assessed these parameters following vildagliptin treatment. Methods: Data were pooled from all double-blind, randomized, controlled, vildagliptin monotherapy trials on previously drug-naïve patients with type 2 diabetes mellitus who received vildagliptin 50 mg once daily (qd or twice daily (bid; n=2,108 and wherein BP and fasting lipid data were obtained. Results: Data from patients receiving vildagliptin 50 mg qd or bid showed reductions from baseline to week 24 in systolic BP (from 132.5±0.32 to 129.8±0.34 mmHg; P<0.0001, diastolic BP (from 81.2±0.18 to 79.6±0.19 mmHg; P<0.0001, fasting triglycerides (from 2.00±0.02 to 1.80±0.02 mmol/L; P<0.0001, very low density lipoprotein cholesterol (from 0.90±0.01 to 0.83±0.01 mmol/L; P<0.0001, and low density lipoprotein cholesterol (from 3.17±0.02 to 3.04±0.02 mmol/L; P<0.0001, whereas high density lipoprotein cholesterol increased (from 1.19±0.01 to 1.22±0.01 mmol/L; P<0.001. Weight decreased by 0.48±0.08 kg (P<0.001. Conclusion: This large pooled analysis demonstrated that vildagliptin shows a significant reduction in BP and a favorable fasting lipid profile that are associated with modest weight loss. Keywords: TG, HDL, LDL, body weight DPP-4 inhibitor, GLP-1 

  16. Spent fuel storage pool

    International Nuclear Information System (INIS)

    Murakami, Naoshi.

    1996-01-01

    Fences are disposed to a fuel exchange floor surrounding the upper surface of a fuel pool for preventing overflow of pool water. The fences comprise a plurality of flat boards arranged in parallel with each other in the longitudinal direction while being vertically inclined, and slits are disposed between the boards for looking down the pool. Further, the fences comprise wide boards and are constituted so as to be laid horizontally on the fuel exchange floor in a normal state and uprisen by means of the signals from an earthquake sensing device. Even if pool water is overflow from the fuel pool by the vibrations occurred upon earthquake and flown out to the floor of the fuel exchange floor, the overflow from the fuel exchange floor is prevented by the fences. An operator who monitors the fuel pool can observe the inside of the fuel pool through the slits formed to the fences during normal operation. The fences act as resistance against overflowing water upon occurrence of an earthquake thereby capable of reducing the overflowing amount of water due to the vibrations of pool water. The effect of preventing overflowing water can be enhanced. (N.H.)

  17. Collaborative Car Pooling System

    OpenAIRE

    João Ferreira; Paulo Trigo; Porfírio Filipe

    2009-01-01

    This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

  18. 13 CFR 120.611 - Pools backing Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pools backing Pool Certificates. 120.611 Section 120.611 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Certificates § 120.611 Pools backing Pool Certificates. (a) Pool characteristics. As set...

  19. Gated blood-pool SPECT assessment of Wolff-Parkinson-White syndromes before and after radiofrequency ablation of accessory pathways; Evaluation fonctionnelle par tomographie cavitaire du syndrome de Wolff-Parkinson-White, avant et apres traitement par radiofrequence

    Energy Technology Data Exchange (ETDEWEB)

    Bontemps, L.; Ben Brahim, H.; Kraiem, T.; Chevalier, P.; Kirkorian, G.; Touboul, P.; Itti, R. [Hopital Cardiologique de Lyon, 69 (France)

    1997-08-01

    Radiofrequency (RF) ablation of accessory pathways in Wolff-Parkinson-White (WPW) syndrome is supposed to be less aggressive than fulguration while providing excellent results. The aims of our study were therefore the evaluation of the functional results of this therapy in terms of left or right ejection fractions and its effects on the contraction synchronism between both ventricular chambers, derived from bi-ventricular Fourier phase histograms. A consecutive series of 44 patients has been investigated within 48 hours before and after RF therapy: 14 patients had right sided WPW and 30 patients left sided WPW. Only patients for whom RF treatment was considered as a success have been included in the study. Gated blood pool tomography has been performed in order to localize the site of pre-excitation and to build-up the phase histograms for both ventricles, and planar gated imaging has been used for right and left ejection fraction determination. Functional results demonstrate the absence of deleterious effect of RF on ventricular contraction and rather a slight increase of ejection fractions, with a more statistically significant difference for left WPW (LVEF = 62.2 % before RF vs 64.4 % after RF; p = 0.02) than for right WPW (RVEF = 36.3 % before RF vs 39.7 after RF; p = 0.16). Phase analysis, on the contrary, show only significant differences for right WPW, with a noticeable decrease of the pre-excitation (left-to-right phase difference 14.4 deg before RF vs 7.5 deg after RF; p = 0.03) and a significant reduction of the right ventricular phase dispersion (right phase standard deviation 26.5 deg before RF vs 19.0 deg after RF; p = 0.03). For left WPW no measurable differences can be demonstrated in the basal state and it is suggested to use stimulation techniques in order to enhance the competition between the normal and accessory conduction pathways. (authors). 17 refs.

  20. 0.125 mm(3) spatial resolution steady-state MR angiography of the thighs with a blood pool contrast agent using the quadrature body coil only at 1.5 Tesla.

    Science.gov (United States)

    Boschewitz, Jack M; Hadizadeh, Dariusch R; Kukuk, Guido M; Meyer, Carsten; Wilhelm, Kai; Koscielny, Arne; Verrel, Frauke; Gieseke, Jürgen; Schild, Hans H; Willinek, Winfried A

    2014-10-01

    To implement and evaluate high spatial resolution three-dimensional MR contrast-enhanced angiography (3D-CEMRA) of the thighs using a blood pool contrast agent (BPCA) using the quadrature body coil only in patients with peripheral arterial occlusive disease (PAOD) in cases receiver coils cannot be used at 1.5 Tesla (T). Nineteen patients (mean age: 68.7 ± 11.2 years; range, 38-83 years) with known PAOD (Fontaine stages; III: 16, IV: 3) prospectively underwent 3D-CEMRA at 1.5T with a noninterpolated voxel size of 0.49 × 0.49 × 0.48 mm(3) . Digital subtraction angiography (DSA) was available for comparison in all patients. Two readers independently evaluated movement artifacts, overall image quality of 3D-CEMRA, and grade of stenosis as compared to DSA. SNR and CNR levels were quantified. The 3D-CEMRA was successfully completed in all patients. Patient movement artifacts that affected stenosis grading occurred in 3/38 thighs. Overall image quality was rated excellent in 15/38, good in 12/38, and diagnostic in 8/38 thighs. Stenosis grading matched with that in DSA in 35/38 thighs. High SNR and CNR were measured in all vessels. The 0.125 mm(3) spatial resolution 3D-CEMRA of the thighs with a BPCA is feasible using a quadrature body coil exclusively with excellent image quality despite long acquisition times. J. Magn. Reson. Imaging 2014;40:996-1001. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  1. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  2. Swimming Pool Safety

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

  3. Vitamin D Pooling Project

    Science.gov (United States)

    The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

  4. Swimming pool special; Zwembadspecial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

  5. Right Ventricular Ejection Fraction using ECG-Gated First Pass Cardioangiography

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Young Hee; Lee, Hae Giu; Lee, Sung Yong; Park, Suk Min; Chung, Soo Kyo; Yim, Jeong Ik; Bahk, Yong Whee; Shinn, Kyung Sub; Kim, Young Gyun; Kwon, Soon Seog [Catholic University College of Medicine, Seoul (Korea, Republic of)

    1993-03-15

    Radionuclide cardioangiography has been widely applied and has played major roles in moninvasive assessment of cardiac function. Three techniques, first-pass gated first and gated equilibrium methods have commonly been used to evaluate right ventricular ejection fraction which usually abnormal in the patients with cardiopulmonary disease. It has been known that the gated first pass method is most accurate method among the three techniques in assessment of fight ventricular ejection fraction. The radionuclide right ventricular ejection fraction values were determined in 13 normal subjects and in 15 patients with chronic obstructive pulmonary disease by the gated first pass method and compared with those of the first pass method because there has been no published data of fight ejection fraction by the gated first pass method were compared with the defects from the pulmonary function test performed in the patients with chronic obstructive pulmomary disease. The results were as follows; 1) The values of fight ventricular ejection fraction by the gated first pass method were 50.1 +- 6.1% in normal subjects and 38.5 +- 8.5 in the patients with chronic obstructive pulmonary disease. There was statistically significant difference between the right ventricular ejection fraction of each of the two groups (p<0.05) 2) The right ventricular ejection fraction by the gated first pass method was not linearly correlated ith FEV{sub 1}, VC. DLCO. and FVC as well as P{sub a}O2 and P{sub a}CO2 of the patients with chronic obstructive pulmonary disease. We concluded that right ventricular ejection fraction by the gated first pass method using radionuclide cardioangiography may be useful in clinical assessment of the right ventricular function.

  6. Reproducibility of ECG-gated Ultrasound Diameter Assessment of Small Abdominal Aortic Aneurysms

    DEFF Research Database (Denmark)

    Bredahl, K; Eldrup, N; Meyer, C

    2013-01-01

    No standardised ultrasound procedure to obtain reliable growth estimates for abdominal aortic aneurysms (AAA) is currently available. We investigated the feasibility and reproducibility of a novel approach controlling for a combination of vessel wall delineation and cardiac cycle variation....

  7. Limited value of interlaced ECG-gated radiography in the presence of a normal chest radiograph

    International Nuclear Information System (INIS)

    Chen, J.T.T.; Ravin, C.E.; Handel, D.

    1984-01-01

    Twenty-seven patients with normal posteroanterior and lateral chest radiographs, who were undergoing cardiac catheterization because of symptoms strongly suggesting coronary artery disease, also had posteroanterior and lateral interlaced electrocardiogram-gated radiographs made. In 14 patients, the interlaced radiography system underestimated (suggested hypokinesia) the wall motion, which was normal on cardiac catheterization. In two cases the system overestimated the wall motion, in two others it both under- and overestimated the motion, and in only nine cases was the correlation correct. These data suggest that the technique is of limited application, particularly in cases in which the routine chest radiographs are normal

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  9. 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.

  10. Evaluation of regional wall motion in myocardial infarction using animation ECG gated cardiac computed tomography

    International Nuclear Information System (INIS)

    Shimizu, Takahiko; Hyodo, Haruo; Hayashi, Terumi; Yamamoto, Hideo; Yagi, Shigeru

    1984-01-01

    Regional wall motion of the left ventricle was evaluated in 21 patients with myocardial infarction using an animation system of gated cardiac computed tomographic (CT) images (animation gated CCT). The results obtained were compared with data by two-dimensional echocardiography (2-DE). 1. Evaluation of the asynergic area by animation gated CCT and 2-DE: Animation gated CCT detected the following specific regions with asynergy established by 2-DE; 10/10 cases (100%) at the anterior wall of the left ventricle, 14/14 cases (100%) at the interventricular septum, and 9/11 cases (81.8%) at the infero-posterior wall. In addition, one false positive case and one negative case were observed at the lateral wall and the apex, respectively. Of 37 instances with asynergic areas established by 2-DE, 21 cases or 89.2% were detected by animation gated CCT; the sensitivity was 91.9%. 2. Evaluation of severity of asynergy by animation gated CCT and 2-DE: The degree of asynergy evaluated by both methods was compared with each other, and the agreement was as follows: 10/10 cases (100%) at the left-ventricular anterior wall, 13/13 cases (100%) at the interventricular septum, and 7/9 cases (77.8%) at the infero-posterior wall. 3. Evaluation of the asynergic area by nonanimation gated CCT and 2-DE: Nonanimation gated CCT detected asynergic areas ascertained by 2-DE at the following areas; 8/10 cases (80%) at the left-ventricular anterior wall, 12/14 cases (85.7%) at the interventricular septum, and 4/11 cases (36.4%) at the infero-posterior wall. The difference between animation and nonanimation gated CCT was statistically significant (p<0.05). The severity of asynergy could not be evaluated by nonanimation gated CCT. (J.P.N.)

  11. Real-time QRS detection using integrated variance for ECG gated cardiac MRI

    Directory of Open Access Journals (Sweden)

    Schmidt Marcus

    2016-09-01

    Full Text Available During magnetic resonance imaging (MRI, a patient’s vital signs are required for different purposes. In cardiac MRI (CMR, an electrocardiogram (ECG of the patient is required for triggering the image acquisition process. However, a reliable QRS detection of an ECG signal acquired inside an MRI scanner is a challenging task due to the magnetohydrodynamic (MHD effect which interferes with the ECG. The aim of this work was to develop a reliable QRS detector usable inside the MRI which also fulfills the standards for medical devices (IEC 60601-2-27. Therefore, a novel real-time QRS detector based on integrated variance measurements is presented. The algorithm was trained on ANSI/AAMI EC13 test waveforms and was then applied to two databases with 12-lead ECG signals recorded inside and outside an MRI scanner. Reliable results for both databases were achieved for the ECG signals recorded inside (DBMRI: sensitivity Se = 99.94%, positive predictive value +P = 99.84% and outside (DBInCarT: Se = 99.29%, +P = 99.72% the MRI. Due to the accurate R-peak detection in real-time this can be used for monitoring and triggering in MRI exams.

  12. ECG-gated myocardial tomo-scintigraphy by rotating bilateral collimator. Clinical application and artificial defect

    Energy Technology Data Exchange (ETDEWEB)

    Komatani, Akio; Takahashi, Kazuei; Takanashi, Toshiyasu; Yamaguchi, Koichi [Yamagata Univ. (Japan)

    1985-01-01

    Tomo-scintigraphy of /sup 201/Tl-myocardium by rotating bilateral collimator was performed in synchronization with cardiac cycle. Ten frames per R-R interval were acquired with ECG pulse signal during 16 min and tomographic reconstruction of end-diastolic and end-systolic image was done. This method was very useful to estimate not only three dimensional distribution of Tl-201, but also wall motion and change of wall thickness during cardiac cycle. However, through its clinical application, artificial defect was frequently noticed at inferior-apical portion of the myocardium. In order to elucidate the cause of the artifact, influence of tilted projection and cardiac motion due to respiratory was also investigated. During inspiratory phase of patients in rest, increment of volume up to 40% and 15 mm of caudal deviation of the left ventricle were observed. Furthermore, periodic motion of the diaphragm interrupted emission of gamma ray from the myocardium. It is proved that main cause of the artifact was not tilting projection, but these influence of respiratory motion.

  13. Preclinical evaluation of carbon-11 and fluorine-18 sulfonamide derivatives for in vivo radiolabeling of erythrocytes

    OpenAIRE

    Gheysens, Olivier; Akurathi, Vamsidhar; Chekol, Rufael; Dresselaers, Tom; Celen, Sofie; Koole, Michel; Dauwe, Dieter; Cleynhens, Bernard J; Claus, Piet; Janssens, Stefan; Verbruggen, Alfons M; Nuyts, Johan; Himmelreich, Uwe; Bormans, Guy M

    2013-01-01

    Background To date, few PET tracers for in vivo labeling of red blood cells (RBCs) are available. In this study, we report the radiosynthesis and in vitro and in vivo evaluation of 11C and 18F sulfonamide derivatives targeting carbonic anhydrase II (CA II), a metallo-enzyme expressed in RBCs, as potential blood pool tracers. A proof-of-concept in vivo imaging study was performed to demonstrate the feasibility to assess cardiac function and volumes using electrocardiogram (ECG)-gated positron ...

  14. Intra-patient variability of FDG standardized uptake values in mediastinal blood pool, liver, and myocardium during R-CHOP chemotherapy in patients with diffuse large B- cell lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Jeong; Yi, Hyun Kyung; Lim, Chae Hong; Cho, Young Seok; Choi, Joon Young; Choe, Yeam Seong; Lee, Kyung Han; Moon, Seung Hwan [Dept. of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2016-12-15

    {sup 18}F-fluorodeoxyglucose (FDG) PET/CT is useful for staging and evaluating treatment response in patients with diffuse large B-cell lymphoma (DLBCL). A five-point scale model using the mediastinal blood pool (MBP) and liver as references is a recommended method for interpreting treatment response. We evaluated the variability in standardized uptake values (SUVs) of the MBP, liver, and myocardium during chemotherapy in patients with DLBCL. We analyzed 60 patients with DLBCL who received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) treatment and underwent baseline, interim, and final FDG PET/CT scans. The FDG uptakes of lymphoma lesions, MBP, liver, and myocardium were assessed, and changes in the MBP and liver SUV and possible associated factors were evaluated. The SUV of the liver did not change significantly during the chemotherapy. However, the SUV{sub mean} of MBP showed a significant change though the difference was small (p = 0.019). SUV{sub mean} of MBP and liver at baseline and interim scans was significantly lower in patients with advanced Ann Arbor stage on diagnosis. The SUV{sub mean} of the MBP and liver was negatively correlated with the volumetric index of lymphoma lesions in baseline scans (r = -0.547, p < 0.001; r = -0.502, p < 0.001). Positive myocardial FDG uptake was more frequently observed in interim and final scans than in the baseline scan, but there was no significant association between the MBP and liver uptake and myocardial uptake. The SUV of the liver was not significantly changed during R-CHOP chemotherapy in patients with DLBCL, whereas the MBP SUV of the interim scan decreased slightly. However, the SUV of the reference organs may be affected by tumor burden, and this should be considered when assessing follow-up scans. Although myocardial FDG uptake was more frequently observed after R-CHOP chemotherapy, it did not affect the SUV of the MBP and liver.

  15. Pool water cleaning facility

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

    1998-05-29

    Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

  16. Noninvasive determination of myocardial blood flow, oxygen consumption and efficiency in normal humans by carbon-11 acetate positron emission tomography imaging

    International Nuclear Information System (INIS)

    Porenta, G.; Cherry, S.; Czernin, J.; Brunken, R.; Kuhle, W.; Hashimoto, T.; Schelbert, H.R.

    1999-01-01

    The aims of this study were: (1) to measure noninvasively and near simultaneously myocardial blood flow, oxygen consumption, and contractile function and (2) to analyze myocardial energy expenditure and efficiency at rest and during dobutamine stress in normal humans. Dynamic and gated carbon-11 acetate positron emission tomography (PET) imaging was performed in 11 normal subjects. The initial uptake of 11 C-acetate was measured to estimate myocardial blood flow. Oxygen consumption was derived from the monoexponential slope of the 11 C-clearance curve recorded during myocardial washout. ECG-gated systolic and diastolic images were acquired during the peak myocardial 11 C activity to measure left ventricular radius, myocardial wall thickness, and long axis length. Myocardial oxygen consumption and parameters of cardiac geometry were used to determine myocardial energetics and cardiac efficiency by tension-area area analysis. Myocardial blood flow averaged 0.8±0.06 ml min -1 g -1 at rest and 1.48±0.15 ml min -1 g -1 during dobutamine stress. Oxygen delivery and consumption were 151±13 and 88±15 μl O 2 min -1 g -1 at rest and increased to 291±31 and 216±31 μl O 2 min -1 g -1 , respectively, during pharmacological stress (P 11 C acetate imaging provides the unique capability to study noninvasively determinants of myocardial energy delivery, expenditure, and efficiency. (orig.)

  17. Liquid sodium pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

    1979-03-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  18. Income pooling within families

    DEFF Research Database (Denmark)

    Bonke, Jens; Uldall-Poulsen, Hans

    This paper analyses the phenomenon of income-pooling by applying the Danish household expenditure survey, merged with authoritative register information. Responses to additional questions on income sharing among 1696 couples also allows us to analyses whether the intra-household distribution...

  19. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  20. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  1. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Roebert, G.A.

    1978-01-01

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  2. Fuel assembly storage pool

    International Nuclear Information System (INIS)

    Hiranuma, Hiroshi.

    1976-01-01

    Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

  3. CERN Electronics Pool presentations

    CERN Multimedia

    2011-01-01

    The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

  4. Analysis and clinical usefullness of cardiac ECT images

    International Nuclear Information System (INIS)

    Hayashi, Makoto; Kagawa, Masaaki; Yamada, Yukinori

    1983-01-01

    We estimated basically and clinically myocardial ECT image and ECG gated cardiac blood-pool ECT image. ROC curve is used for the evaluation of the accuracy in diagnostic myocardial infarction. The accuracy in diagnostic of MI is superior in myocardial ECT image and ECT estimation is unnecessary skillfulness and experience. We can absene the whole defect of MI than planar image by using ECT. LVEDV between estimated volume and contrast volume is according to it and get one step for automatic analysis of cardiac volume. (author)

  5. The value of radionuclide phase analysis and parameters of cardial function for diagnosis CAD at rest and during exercise

    International Nuclear Information System (INIS)

    Huang Gang

    1990-01-01

    27 patients and 5 normal were studied with ECG-gated cardial blood pool images and radionuclide phase analysis at rest and during exercise. The results showed that the sensitivity of LVEF in CAD at rest and during exercise were 57% and 71% respectively, and the sensitivity of the ventricular phase in CAD were 79% at rest and 90% during exercise, and the sensitivity of phase angle in CAD were higher than of LVEF. This suggested that the ventricular phase angle was important for diagnosing early CAD. In addition, regional EF, phase image and ventricular wall motion were useful to detect the lesion of ischemia in CAD

  6. Electrocardiographic gating in positron emission computed tomography

    International Nuclear Information System (INIS)

    Hoffman, E.J.; Phelps, M.E.; Wisenberg, G.; Schelbert, H.R.; Kuhl, D.E.

    1979-01-01

    Electrocardiographic (ECG) synchronized multiple gated data acquisition was employed with positron emission computed tomography (ECT) to obtain images of myocardial blood pool and myocardium. The feasibility and requirements of multiple gated data acquisition in positron ECT were investigated for 13NH3, ( 18 F)-2-fluoro-2-D-deoxyglucose, and ( 11 C)-carboxyhemoglobin. Examples are shown in which image detail is enhanced and image interpretation is facilitated when ECG gating is employed in the data collection. Analysis of count rate data from a series of volunteers indicates that multiple, statistically adequate images can be obtained under a multiple gated data collection format without an increase in administered dose

  7. Swimming Pools and Molluscum Contagiosum

    Science.gov (United States)

    ... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

  8. Pool-type reactor

    International Nuclear Information System (INIS)

    Hopkins, S.R.

    1977-01-01

    This invention relates to a pool nuclear reactor fitted with a perfected system to raise the buckets into a vertical position at the bottom of a channel. This reactor has an inclined channel to guide a bucket containing a fuel assembly to introduce it into the reactor jacket or extract it therefrom and a damper at the bottom of the channel to stop the drop of the bucket. An upright vertically movable rod has a horizontally articulated arm with a hook. This can pivot to touch a radial lug on the bucket and pivot the bucket around its base in a vertical position, when the rod moves up [fr

  9. Human parvovirus PARV4 in plasma pools of Chinese origin.

    Science.gov (United States)

    Ma, Y-Y; Guo, Y; Zhao, X; Wang, Z; Lv, M-M; Yan, Q-P; Zhang, J-G

    2012-10-01

    Human parvovirus 4 (PARV4) is present in blood and blood products. As the presence and levels of PARV4 in Chinese source plasma pools have never been determined, we implemented real-time quantitative PCR to investigate the presence of PARV4 in source plasma pools in China. Results showed that 26·15% (51/195) of lots tested positive for PARV4. The amounts of DNA ranged from 2·83 × 10(3) copies/ml to 2·35×10(7) copies/ml plasma. The high level of PARV4 in plasma pools may pose a potential risk to recipients. Further studies on the pathogenesis of PARV4 are urgently required. © 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.

  10. Model of large pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

    2006-08-21

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

  11. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  12. Design of hydrotherapy exercise pools.

    Science.gov (United States)

    Edlich, R F; Abidin, M R; Becker, D G; Pavlovich, L J; Dang, M T

    1988-01-01

    Several hydrotherapy pools have been designed specifically for a variety of aquatic exercise. Aqua-Ark positions the exerciser in the center of the pool for deep-water exercise. Aqua-Trex is a shallow underwater treadmill system for water walking or jogging. Swim-Ex generates an adjustable laminar flow that permits swimming without turning. Musculoskeletal conditioning can be accomplished in the above-ground Arjo shallow-water exercise pool. A hydrotherapy pool also can be custom designed for musculoskeletal conditioning in its shallow part and cardiovascular conditioning in a deeper portion of the pool. Regardless of the type of exercise, there is general agreement that the specific exercise conducted in water requires significantly more energy expenditure than when the same exercise is performed on land.

  13. ENERGY STAR Certified Pool Pumps

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.1 ENERGY STAR Program Requirements for Pool Pumps that are effective as of February 15,...

  14. Pooling and correlated neural activity

    Directory of Open Access Journals (Sweden)

    Robert Rosenbaum

    2010-04-01

    Full Text Available Correlations between spike trains can strongly modulate neuronal activity and affect the ability of neurons to encode information. Neurons integrate inputs from thousands of afferents. Similarly, a number of experimental techniques are designed to record pooled cell activity. We review and generalize a number of previous results that show how correlations between cells in a population can be amplified and distorted in signals that reflect their collective activity. The structure of the underlying neuronal response can significantly impact correlations between such pooled signals. Therefore care needs to be taken when interpreting pooled recordings, or modeling networks of cells that receive inputs from large presynaptic populations. We also show that the frequently observed runaway synchrony in feedforward chains is primarily due to the pooling of correlated inputs.

  15. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  16. Sustainability of common pool resources

    OpenAIRE

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepales...

  17. Seismic analysis of large pools

    Energy Technology Data Exchange (ETDEWEB)

    Dong, R.G.; Tokarz, F.J.

    1976-11-17

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

  18. Seismic analysis of large pools

    International Nuclear Information System (INIS)

    Dong, R.G.; Tokarz, F.J.

    1976-01-01

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

  19. Step-and-shoot prospectively ECG-gated versus retrospectively ECG-gated with tube current modulation coronary CT angiography using the 128-slice MDCT: comparison of image quality and radiation dose

    International Nuclear Information System (INIS)

    Jeong, Dong Wook; Choo, Ki Seok; Baik, Seung Kug; Kim, Yong Woo; Jeon, Ung Bae; Kim, Jeong Soo; Lim, Soo Jin

    2011-01-01

    Background: Little is known regarding image quality and the required radiation dose for step-and-shoot and retrospective coronary computed tomography angiography (CCTA) with tube current modulation (TCM) in 128-slice multidetector CT (MDCT) coronary angiography. Purpose: To compare image quality and radiation dose in patients who underwent 128-slice MDCT by the step-and- shoot method with those in patients who underwent 128-slice MDCT with retrospective CCTA with TCM. Material and Methods: CCTA obtained with 128-slice MDCT was retrospectively evaluated in 160 patients. Two independent reviewers separately scored the subjective image quality of the coronary artery segments (1, excellent; 4, poor) for step-and-shoot (68, mean heart rate [HR]: 59.3±6.8) and retrospective CCTA with TCM (77, mean HR: 59.1±9.8). Interobserver variability was calculated. Effective radiation doses of both scan techniques were calculated with dose-length product. Results: There was good agreement for quality scores of coronary artery segment images between the independent reviewers (k=0.72). The number of coronary artery segments that could not be evaluated was 2.85% (27 of 947) in the step-and-shoot and 1.87% (20 of 1071) in retrospective CCTA with TCM. Image quality scores were not significantly different (P>.05). Mean patient radiation dose was 63% lower for step-and-shoot (1.94±0.70 mSv) than for retrospective CCTA with TCM (4.51±1.18 mSv) (P<0.0001). For patients who underwent step-and-shoot or retrospective CCTA with TCM, an average HR of 63.5 beats per minute was identified as the threshold for the prediction of non-diagnostic image quality for both protocols. There were no significant differences in the image quality of both methods between obese (body mass index [BMI≥25) and non-obese patients (BMI<25), but radiation doses were higher in the obesity group than in the non-obesity group for both methods. Conclusion: Both step-and-shoot and retrospective CCTA with TCM using 128-slice MDCT had similar subjective image quality scores, but step-and-shoot required a lower radiation dose than retrospective CCTA with TCM

  20. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

  1. Patent pools: Intellectual property rights and competition.

    NARCIS (Netherlands)

    Rodriguez, V.F.

    2010-01-01

    Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

  2. Inter-observer variation in estimates by nuclear angiography of left ventricular ejection fraction and ejection rate

    International Nuclear Information System (INIS)

    Young, K.C.; Railton, R.

    1980-01-01

    The recent decline in the cost of computing has led to the introduction of data processing of gamma-camera images in many medical centres, allowing the development and widespread use of radionuclide techniques for assessing left ventricular performance. Methods such as ECG-gated blood-pool imaging have the advantage of being less invasive than contrast ventriculography and do not rely on geometrical assumptions about the shape of the ventricle. A study has been made of the inter-observer variation in estimates of ejection fraction and average and maximum systolic contraction rates using a micro-computer (VIP-450 Video Image Processor, Ohio-Nuclear Limited, Rugby) to analyse gated blood-pool images of the left ventricle. (author)

  3. Ventricular Geometry From Non-contrast Non-ECG-gated CT Scans: An Imaging Marker of Cardiopulmonary Disease in Smokers.

    Science.gov (United States)

    Rahaghi, Farbod N; Vegas-Sanchez-Ferrero, Gonzalo; Minhas, Jasleen K; Come, Carolyn E; De La Bruere, Isaac; Wells, James M; González, Germán; Bhatt, Surya P; Fenster, Brett E; Diaz, Alejandro A; Kohli, Puja; Ross, James C; Lynch, David A; Dransfield, Mark T; Bowler, Russel P; Ledesma-Carbayo, Maria J; San José Estépar, Raúl; Washko, George R

    2017-05-01

    Imaging-based assessment of cardiovascular structure and function provides clinically relevant information in smokers. Non-cardiac-gated thoracic computed tomographic (CT) scanning is increasingly leveraged for clinical care and lung cancer screening. We sought to determine if more comprehensive measures of ventricular geometry could be obtained from CT using an atlas-based surface model of the heart. Subcohorts of 24 subjects with cardiac magnetic resonance imaging (MRI) and 262 subjects with echocardiography were identified from COPDGene, a longitudinal observational study of smokers. A surface model of the heart was manually initialized, and then automatically optimized to fit the epicardium for each CT. Estimates of right and left ventricular (RV and LV) volume and free-wall curvature were then calculated and compared to structural and functional metrics obtained from MRI and echocardiograms. CT measures of RV dimension and curvature correlated with similar measures obtained using MRI. RV and LV volume obtained from CT inversely correlated with echocardiogram-based estimates of RV systolic pressure using tricuspid regurgitation jet velocity and LV ejection fraction respectively. Patients with evidence of RV or LV dysfunction on echocardiogram had larger RV and LV dimensions on CT. Logistic regression models based on demographics and ventricular measures from CT had an area under the curve of >0.7 for the prediction of elevated right ventricular systolic pressure and ventricular failure. These data suggest that non-cardiac-gated, non-contrast-enhanced thoracic CT scanning may provide insight into cardiac structure and function in smokers. Copyright © 2017. Published by Elsevier Inc.

  4. Can ECG-gated MDCT be considered an obligatory step to plan and manage a new chest-pain unit?

    International Nuclear Information System (INIS)

    Runza, G.; Alaimo, V.; La Grutta, L.; Galia, M.; Basile, A.; Cademartiri, F.; Krestin, G.P.; Midiri, M.

    2007-01-01

    The recent improvements in multi-detector computed tomography technology and its application in cardiac field allow to consider this non-invasive imaging technique as a promising comprehensive method for detecting significant coronary stenoses in a chest-pain unit. The possibility to use the ECG-synchronisation acquisition protocol, normally limited to the cardiac volume, for the entire thoracic vascular system should have the remarkable potential to reduce invasive and non-invasive procedures actually used to investigate acute chest pain and the number of unnecessary hospital admissions without reducing appropriate admissions in patients with chest pain

  5. A correlative study of aortic valve rotation angle and thoracic aortic sizes using ECG gated CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saremi, Farhood, E-mail: fsaremi@usc.edu; Cen, Steven; Tayari, Nazila; Alizadeh, Houman; Emami, Amir; Lin, Leah; Fleischman, Fernando

    2017-04-15

    Objective: Various degrees of aortic valve rotation may be seen in individuals with no history of congenital cardiovascular malformations, but its association with aortic sizes has not been studied. Methods: Gated computed tomographic (CT angiograms in 217 patients were studied (66.7 ± 15; 22–97 years old)). Aortic diameters were determined at 5 anatomic locations. The length of the aorta from sinus to left subclavian artery was measured. The angle of valve rotation was recorded by measuring the angle between a line connecting the midpoint of the non-coronary sinus to the anterior commissure and another line along the interatrial septum. Rotation angles were correlated with aortic measurements. Patients were separated into two groups based on aortic sizes and into three groups based on age. The threshold for aortic dilatation was set at maximum ascending aorta diameter ≥40 mm (≥21 mm body surface area [BSA] indexed). Results: No significant difference in rotation angles was seen between the three age groups or between genders. Rotation angles were significantly correlated with maximal, average, and BSA adjustment of the aortic root and ascending aortic measurements. The aortic root angles were significantly different between the dilated versus nondilated aortas. There was no significant association between the rotation angles and age, length of ascending aorta, or diameters of descending aorta. Multivariate adaptive regression splines showed 25° of aortic root rotation as the diagnostic cut off for ascending aorta dilation. Above the 25° rotation, every 10° of increasing rotation was associated with a 3.78 ± 0.87 mm increase in aortic diameter (p < 0.01) and a 1.73 ± 0.25 times increased risk for having a dilated aorta (p < 0.01). Conclusion: Rotation angles of the aortic valve may be an independent non-invasive imaging marker for dilatation of the ascending aorta. Patients with increased rotation angle of the aortic valve may have higher risk for development or acceleration of an ascending aortic dilatation.

  6. Prospective ECG triggering reduces prosthetic heart valve-induced artefacts compared with retrospective ECG gating on 256-slice CT

    NARCIS (Netherlands)

    Symersky, P.; Habets, J.; Westers, P.; Mol, de B.A.J.M.; Prokop, M.; Budde, R.P.J.

    2012-01-01

    Objectives Multidetector computed tomography (MDCT) has diagnostic value for the evaluation of prosthetic heart valve (PHV) dysfunction but it is hampered by artefacts. We hypothesised that image acquisition using prospective triggering instead of retrospective gating would reduce artefacts related

  7. Assessment of Myocardial Bridge and Mural Coronary Artery Using ECG-Gated 256-Slice CT Angiography: A Retrospective Study

    Directory of Open Access Journals (Sweden)

    En-sen Ma

    2013-01-01

    Full Text Available Recent clinical reports have indicated that myocardial bridge and mural coronary artery complex (MB-MCA might cause major adverse cardiac events. 256-slice CT angiography (256-slice CTA is a newly developed CT system with faster scanning and lower radiation dose compared with other CT systems. The objective of this study is to evaluate the morphological features of MB-MCA and determine its changes from diastole to systole phase using 256-slice CTA. The imaging data of 2462 patients were collected retrospectively. Two independent radiologists reviewed the collected images and the diagnosis of MB-MCA was confirmed when consistency was obtained. The length, diameter, and thickness of MB-MCA in diastole and systole phases were recorded, and changes of MB-MCA were calculated. Our results showed that among the 2462 patients examined, 336 have one or multiple MB-MCA (13.6%. Out of 389 MB-MCA segments, 235 sites were located in LAD2 (60.41%. The average diameter change of MCA in LAD2 from systole phase to diastole phase was  mm, and 34.9% of MCA have more than 50% diameter stenosis in systole phase. This study suggested that 256-slice CTA multiple-phase reconstruction technique is a reliable method to determine the changes of MB-MCA from diastole to systole phase.

  8. Efficient pooling designs for library screening

    OpenAIRE

    Bruno, William J.; Knill, Emanuel; Balding, David J.; Bruce, D. C.; Doggett, N. A.; Sawhill, W. W.; Stallings, R. L.; Whittaker, Craig C.; Torney, David C.

    1994-01-01

    We describe efficient methods for screening clone libraries, based on pooling schemes which we call ``random $k$-sets designs''. In these designs, the pools in which any clone occurs are equally likely to be any possible selection of $k$ from the $v$ pools. The values of $k$ and $v$ can be chosen to optimize desirable properties. Random $k$-sets designs have substantial advantages over alternative pooling schemes: they are efficient, flexible, easy to specify, require fewer pools, and have er...

  9. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  10. Sculpting the Barnyard Gene Pool

    Science.gov (United States)

    Childers, Gina; Wolfe, Kim; Dupree, Alan; Young, Sheila; Caver, Jessica; Quintanilla, Ruby; Thornton, Laura

    2016-01-01

    Project-based learning (PBL) takes student engagement to a higher level through reflective collaboration, inquiry, critical thinking, problem solving, and personal relevance. This article explains how six high school teachers developed an interconnected, interdisciplinary STEM-focused PBL called "Sculpting the Barnyard Gene Pool." The…

  11. Methods of gated-blood-pool-spect data processing

    International Nuclear Information System (INIS)

    Kosa, I.; Mester, J.; Tanaka, M.; Csernay, L.; Mate, E.; Szasz, K.

    1991-01-01

    Three techniques of gated SPECT were evaluated. The methods of Integral SPECT (ISPECT), enddyastole-endsystole SPECT (ED-ES SPECT) and Fourier SPECT were adapted and developed on the Hungarian nuclear medicine data processing system microSEGAMS. The methods are based on data reduction before back projection which results in processing times acceptable for the clinical routine. The clinical performance of the introduced techniques was tested in 10 patients with old posterior myocardial infarction and in 5 patients without cardiac disease. The left ventricular ejection faction determined by ISPECT correlated well with the planar values. The correlation coefficient was 0.89. The correlation coefficient of EF values determined by ED-ES SPECT and planar radionuclide ventriculography was lower (0.70). For the identification of left ventricular wall motion abnormalities ED-ES SPECT and Fourier SPECT exhibited a favourable performance, but ISPECT only moderate suitability. In the detection of regional phase delay Fourier-SPECT demonstrated higher sensitivity than the planar radionuclide ventriculography. (author) 4 refs.; 3 figs.; 2 tabs

  12. "Ripples" in an Aluminum Pool?

    Science.gov (United States)

    Rohr, James; Wang, Si-Yin; Nesterenko, Vitali F.

    2018-05-01

    Our motivation for this article is for students to realize that opportunities for discovery are all around them. Discoveries that can still puzzle present day researchers. Here we explore an observation by a middle school student concerning the production of what appears to be water-like "ripples" produced in aluminum foil when placed between two colliding spheres. We both applaud and explore the student's reasoning that the ripples were formed in a melted aluminum pool.

  13. Sustainability of common pool resources.

    Science.gov (United States)

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepalese areas: (i) rural (non-capitalistic) and (ii) urban (capitalistic) areas. We find that a proportion of prosocial individuals in urban areas is lower than that in rural areas, and urban residents deplete resources more quickly than rural residents. The composition of proself and prosocial individuals in a group and the degree of capitalism are crucial in that an increase in prosocial members in a group and the rural dummy positively affect resource sustainability by 65% and 63%, respectively. Overall, this paper shows that when societies move toward more capitalistic environments, the sustainability of common pool resources tends to decrease with the changes in individual preferences, social norms, customs and views to others through human interactions. This result implies that individuals may be losing their coordination abilities for social dilemmas of resource sustainability in capitalistic societies.

  14. Flashing oscillation in pool water

    International Nuclear Information System (INIS)

    Takamasa, Tomoji; Kondo, Koichi; Hazuku, Tatsuya

    1996-01-01

    This paper presents an experimental study of high-pressure saturated water discharging into the pool water. The purpose of the experiment is to clarify the phenomena that occur in blow-down of high-pressure saturated water from the pressure vessel into the water-filled containment in the case of a wall-crack accident or a LOCA in an advanced reactor. The results revealed that a flashing oscillation (FO) occurs when high-pressure saturated water discharges into the pool water, under specified experimental settings. The range of the flashing oscillates between a point very close to and some distance from the vent hole. The pressures in the vent tube and pool water vary according to the flashing oscillation. The pressure oscillation and frequency of flashing position might be caused by the balancing action between the supply of saturated water, flashing at the control volume and its condensation on the steam-water interface. A linear analysis was conducted using a spherical flashing bubble model. The period of the flashing oscillation in the experiments can be explained by theoretical analysis

  15. Pressure supression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-10-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model developed in this work produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing is verified by comparing the model-predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  16. Pressure suppression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-01-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  17. CDC Study Finds Fecal Contamination in Pools

    Science.gov (United States)

    ... Communication (404) 639-3286 CDC study finds fecal contamination in pools A study of public pools done ... The E. coli is a marker for fecal contamination. Finding a high percentage of E. coli-positive ...

  18. 1968 Listing of Swimming Pool Equipment.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

    An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

  19. Method of measuring a liquid pool volume

    Science.gov (United States)

    Garcia, G.V.; Carlson, N.M.; Donaldson, A.D.

    1991-03-19

    A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools is disclosed, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figures.

  20. Large-scale pool fires

    Directory of Open Access Journals (Sweden)

    Steinhaus Thomas

    2007-01-01

    Full Text Available A review of research into the burning behavior of large pool fires and fuel spill fires is presented. The features which distinguish such fires from smaller pool fires are mainly associated with the fire dynamics at low source Froude numbers and the radiative interaction with the fire source. In hydrocarbon fires, higher soot levels at increased diameters result in radiation blockage effects around the perimeter of large fire plumes; this yields lower emissive powers and a drastic reduction in the radiative loss fraction; whilst there are simplifying factors with these phenomena, arising from the fact that soot yield can saturate, there are other complications deriving from the intermittency of the behavior, with luminous regions of efficient combustion appearing randomly in the outer surface of the fire according the turbulent fluctuations in the fire plume. Knowledge of the fluid flow instabilities, which lead to the formation of large eddies, is also key to understanding the behavior of large-scale fires. Here modeling tools can be effectively exploited in order to investigate the fluid flow phenomena, including RANS- and LES-based computational fluid dynamics codes. The latter are well-suited to representation of the turbulent motions, but a number of challenges remain with their practical application. Massively-parallel computational resources are likely to be necessary in order to be able to adequately address the complex coupled phenomena to the level of detail that is necessary.

  1. Structural integrity assessment of HANARO pool cover

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    2001-11-01

    This report is for the seismic analysis and the structural integrity evaluation of HANARO Pool Cover in accordances with the requirement of the Technical Specification for Seismic Analysis of HANARO Pool Cover. For performing the seismic analysis and evaluating the structural integrity for HANARO Pool Cover, the finite element analysis model using ANSYS 5.7 was developed and the dynamic characteristics were analyzed. The seismic response spectrum analyses of HANARO Pool Cover under the design floor response spectrum loads of OBE and SSE were performed. The analysis results show that the stress values in HANARO Pool Cover for the seismic loads are within the ASME Code limits. It is also confirmed that the fatigue usage factor is less than 1.0. Therefore any damage on structural integrity is not expected when an HANARO Pool Cover is installed in the upper part of the reactor pool

  2. Application of single photon ECT for dynamic study

    International Nuclear Information System (INIS)

    Mukai, T.; Ishii, Y.; Tamaki, N.

    1982-01-01

    Feasibility of dynamic study in a form of ECT using a rotating gamma camera was evaluated. Since it takes longer one around time sampling, application for the dynamic study is limited under following conditions; 1) physiological gated process, 2) slow clearance process, 3) physiological steady state process. The gated study was applicated for heart pumping action synchronized with ECG. The ECG gated heart ECT either of blood pool or myocardium was useful to reveal a subtle wall motion abnormalities in a tomographic plane, even when a planar imaging failed to reveal it. As for slow dynamic process of tracer, an excretion process of hepatobiliary agent, was subjected to be analyzed in order to calculate clearance rate at each pixel. As for steady state process, an ECT of regional celebral blood flow (rCBF) was investigated during continuous infusion into intracarotid artery. All of these technique were proved to have a clinical feasibility and to potentiate usefulness of the single photon ECT (SPECT)

  3. Livermore pool-type reactor

    International Nuclear Information System (INIS)

    Mann, L.G.

    1977-01-01

    The Livermore Pool-Type Reactor (LPTR) has served a dual purpose since 1958--as an instrument for fundamental research and as a tool for measurement and calibration. Our early efforts centered on neutron-diffraction, fission, and capture gamma-ray studies. During the 1960's it was used for extensive calibration work associated with radiochemical and physical measurements on nuclear-explosive tests. Since 1970 the principal applications have been for trace-element measurements and radiation-damage studies. Today's research program is dominated by radiochemical studies of the shorter-lived fission products and by research on the mechanisms of radiation damage. Trace-element measurement for the National Uranium Resource Evaluation (NURE) program is the major measurement application today

  4. Arc-weld pool interactions

    International Nuclear Information System (INIS)

    Glickstein, S.S.

    1978-08-01

    The mechanisms involved in arc-weld pool interactions are extremely complex and no complete theory is presently available to describe much of the phenomena observed during welding. For the past several years, experimental and analytical studies have been undertaken at the Bettis Atomic Power Laboratory to increase basic understanding of the gas tungsten arc welding process. These studies have included experimental spectral analysis of the arc in order to determine arc temperature and analytical modeling of the arc and weld puddle. The investigations have been directed toward determining the cause and effects of variations in the energy distribution incident upon the weldment. In addition, the effect of weld puddle distortion on weld penetration was investigated, and experimental and analytical studies of weld process variables have been undertaken to determine the effects of the variables upon weld penetration and configuration. A review of the results and analysis of these studies are presented

  5. Blood pressure

    Science.gov (United States)

    Normal blood pressure is important for proper blood flow to the body's organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart ...

  6. Blood Types

    Science.gov (United States)

    ... blood, safe blood transfusions depend on careful blood typing and cross-matching. There are four major blood ... cause exceptions to the above patterns. ABO blood typing is not sufficient to prove or disprove paternity ...

  7. Guide for decontaminating swimming pool at schools

    International Nuclear Information System (INIS)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-01

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  8. Current operating practices of nuclear insurance pools

    International Nuclear Information System (INIS)

    O'Connell, J.M.

    1993-01-01

    This paper discusses the nuclear pooling system and co-operation between the pools, present practice and capacity, with a breakdown of the limits for third party liability and material damage. The author also describes the relationship between the pools and the nuclear operators (the policyholders), and concludes that the nuclear pools have been successful in serving the interests of their member companies, their policyholders and the governments as they have provided a stable insurance market by making available capacity in amounts that had never before been assembled and placed at risk in a single location. 2 tabs

  9. Guide for decontaminating swimming pool at schools

    Energy Technology Data Exchange (ETDEWEB)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-15

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  10. Structure for nuclear fuel storage pools

    International Nuclear Information System (INIS)

    Ebata, Sakae; Nichiei, Shinji.

    1979-01-01

    Purpose: To enable leak detection in nuclear fuel storage pools, as well as prevent external leakages while keeping the strength of the constructional structures. Constitution: Protection plates are provided around pool linear plates and a leak reception is provided to the bottom. Leakages are detected by leak detecting pipeways and the external leakages are prevented by collecting them in a detection area provided in the intermediate layer. Since ferro-reinforcements at the bottom wall of the pool are disconnected by the protection plate making it impossible to form the constructional body, body hunches are provided to the bottom wall of the pool for processing the ferro-reinforcements. (Yoshino, Y.)

  11. Heat transfer from internally heated hemispherical pools

    International Nuclear Information System (INIS)

    Gabor, J.D.; Ellsion, P.G.; Cassulo, J.C.

    1980-01-01

    Experiments were conducted on heat transfer from internally heated ZnSO 4 -H 2 O pools to the walls of hemispherical containers. This experimental technique provides data for a heat transfer system that has to date been only theoretically treated. Three different sizes of copper hemispherical containers were used: 240, 280, 320 mm in diameter. The pool container served both as a heat transfer surface and as an electrode. The opposing electrode was a copper disk, 50 mm in diameter located at the top of the pool in the center. The top surface of the pool was open to the atmosphere

  12. Depletion of NAD pool contributes to impairment of endothelial progenitor cell mobilization in diabetes.

    Science.gov (United States)

    Wang, Pei; Yang, Xi; Zhang, Zheng; Song, Jie; Guan, Yun-Feng; Zou, Da-Jin; Miao, Chao-Yu

    2016-06-01

    The impaired mobilization of endothelial progenitor cells (EPCs) from bone marrow (BM) critically contributes to the diabetes-associated vascular complications. Here, we investigated the relationship between the nicotinamide phosphoribosyltransferase (NAMPT)-controlled nicotinamide adenine dinucleotide (NAD) metabolism and the impaired mobilization of BM-derived EPCs in diabetic condition. The NAMPT-NAD pool in BM and BM-derived EPCs in wild-type (WT) and diabetic db/db mice was determined. Nicotinamide, a natural substrate for NAD biosynthesis, was administrated for 2weeks in db/db mice to examine the influence of enhancing NAD pool on BM and blood EPCs number. The modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein in BM were measured using immunoblotting. The EPCs intracellular NAMPT level and NAD concentration, as well as the blood EPCs number, were compared between 9 healthy people and 16 patients with type 2 diabetes mellitus (T2DM). The T2DM patients were treated with nicotinamide for two weeks and then the blood EPCs number was determined. Moreover, the association between blood EPCs numbers and EPCs intracellular NAD(+)/NAMPT protein levels in 21 healthy individuals was determined. We found that NAD concentration and NAMPT expression in BM and BM-derived EPCs of db/db mice were significantly lower than those in WT mice BM. Enhancing NAD pool not only increased the EPCs intracellular NAD concentration and blood EPCs number, but also improved post-ischemic wound healing and blood reperfusion in db/db mice with hind-limb ischemia model. Enhancing NAD pool rescued the impaired modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein levels in db/db mice BM upon hind-limb ischemia. In addition, enhancing NAD pool significantly inhibited PARP and caspase-3 activates in db/db mice BM. The intracellular NAMPT-NAD pool was positively associated with blood

  13. Oxidation kinetics of corium pool

    Energy Technology Data Exchange (ETDEWEB)

    Sulatsky, A.A., E-mail: andrei314@mail.ru [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Smirnov, S.A. [D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), St. Petersburg (Russian Federation); Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Fischer, M.; Hellmann, S. [AREVA NP GmbH, Erlangen (Germany); Tromm, W.; Miassoedov, A. [Forschungzentrum Karlsruhe (FZK), Karlsruhe (Germany); Bottomley, D. [EUROPÄISCHE KOMMISSION, Joint Research Centre Institut für Transurane (ITU), Karlsruhe (Germany); Piluso, P. [CEA Cadarache-DEN/DTN/STRI, St.Paul-lez-Durance (France); Barrachin, M. [Institut de Radioprotection et Sûreté Nucléaire, St.Paul-lez-Durance (France)

    2013-09-15

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations.

  14. Oxidation kinetics of corium pool

    International Nuclear Information System (INIS)

    Sulatsky, A.A.; Smirnov, S.A.; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu.; Fischer, M.; Hellmann, S.; Tromm, W.; Miassoedov, A.; Bottomley, D.; Piluso, P.; Barrachin, M.

    2013-01-01

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations

  15. 13 CFR 120.1708 - Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... United States. (c) SBA purchase of a Loan Interest. SBA will determine whether to purchase a Loan... reserves the right to purchase a Loan Interest from a Pool at any time. (d) Self-liquidating. A Pool... market conditions and program experience, and will publish any such change in the Federal Register. (h...

  16. Compact fuel storage rack for fuel pools

    International Nuclear Information System (INIS)

    Parras, F.; Louvat, J.P.

    1986-01-01

    ETS LEMER and FRAMATOME propose a new compact storage rack. This rack permits a considerable increase of the storage capacity of cooling pools. A short description of the structure and the components is presented, to propose racks that are: . Inalterable, . Compact, . Insensitive to earthquakes. Installation in pools already in operation is simplified by their light structure and the bearing device [fr

  17. The warm pool in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shetye, S.R.

    is larger and warmer, a peculiarity of the pool in the Indian Ocean is its seasonal variation. The surface area of the pool changes from 24 x 106 km2 in April to 8 x 106 km2 in September due to interaction with the southwest monsoon. The annual cycles of sea...

  18. Shedding Light on Dark Liquidity Pools

    NARCIS (Netherlands)

    Degryse, H.A.; van Achter, M.; Wuyts, G.

    2008-01-01

    This article reviews the recent developments on dark liquidity pools starting from the theoretical and empirical academic literature. The number of dark liquidity pools as well as their trading volume has grown substantially in the last couple of years. We highlight the incentives of providers as

  19. Big city consultants shut down our pool : a shocking community pool gets checked for stray voltage

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, P. [Power Line Systems Engineering Inc., Markham, ON (Canada)

    2009-12-15

    This article discussed an investigation conducted at a community pool where swimmers complained of receiving electrical shocks both in the pool and on the pool's deck area. Electrical measurements taken at the pool revealed current flows from the pool water to various points around the deck area. Measured current flow in the pool area was 30 amps even when the main pool service breaker was opened to shut off power to the entire facility. Thirty amps of primary neutral current was then measured on the primary side aerial neutral in front of the pool. A 10 amp primary feeder from the pool joined up with the complex's primary neutral wire to increase the neutral current to 40 amps. The combined 40 amps current then returned to the secondary side of a nearby utility transformer substation. The study showed that the underground wet low-resistance grounded surface area of the pool was attracting the 30 amps of utility current from the surrounding ground area. The local utility disconnected the primary and secondary neutral interconnection at the pool's main 600-volt step-down transformer. The pool deck was removed in order to install additional copper bonding grounds. In order to avert serious injuries, many experts propose that all electric utilities should be required by law to reconfigure their power systems to prevent primary power neutral currents from entering private buildings. 1 tab., 2 figs.

  20. Ripples in a superconducting tidal pool

    CERN Document Server

    Hudson, E

    2003-01-01

    The behaviour of electrons in a metal is often compared to that of water in a pool. An empty pool is like a material that has all of its electrons removed. As electrons are 'poured' into the metal, they first occupy the lowest energies available - the bottom of the pool - and eventually fill up to the Fermi energy, the top of the pool. At this point we no longer discuss electrons but quasiparticles. These are electrons that have modified properties due to their interactions within the material. Waves in a pool can be excited, and their properties will depend on the depth of the water. Similarly in a metal, quasiparticles behave like waves that have a material-dependent dispersion relation between their energy and their wavevector, which specifies their direction and wavelength. This simple analogy also hints at an indirect method of measuring the dispersion relation of a metal, and hence the myriad of properties that depend on it. (U.K.)

  1. Design and Construction of Pool Door for Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door.

  2. Design and Construction of Pool Door for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin

    2016-01-01

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door

  3. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  4. Pool scrubbing models for iodine components

    International Nuclear Information System (INIS)

    Fischer, K.

    1996-01-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs

  5. Automatic extraction of myocardial mass and volumes using parametric images from dynamic nongated PET

    DEFF Research Database (Denmark)

    Harms, Hendrik Johannes; Hansson, Nils Henrik Stubkjær; Tolbod, Lars Poulsen

    2016-01-01

    Dynamic cardiac positron emission tomography (PET) is used to quantify molecular processes in vivo. However, measurements of left-ventricular (LV) mass and volumes require electrocardiogram (ECG)-gated PET data. The aim of this study was to explore the feasibility of measuring LV geometry using non......-gated dynamic cardiac PET. METHODS: Thirty-five patients with aortic-valve stenosis and 10 healthy controls (HC) underwent a 27-min 11C-acetate PET/CT scan and cardiac magnetic resonance imaging (CMR). HC were scanned twice to assess repeatability. Parametric images of uptake rate K1 and the blood pool were......LV and WT only and an overestimation for LVEF at lower values. Intra- and inter-observer correlations were >0.95 for all PET measurements. PET repeatability accuracy in HC was comparable to CMR. CONCLUSION: LV mass and volumes are accurately and automatically generated from dynamic 11C-acetate PET without...

  6. Operation and maintenance techniques of pool and pool water purification system in IMEF

    Energy Technology Data Exchange (ETDEWEB)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs.

  7. Operation and maintenance techniques of pool and pool water purification system in IMEF

    International Nuclear Information System (INIS)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs

  8. Swimming pool hydraulics and their significance for public pools. Bedeutung der Beckenhydraulik in oeffentlichen Schwimmbaedern

    Energy Technology Data Exchange (ETDEWEB)

    Gansloser, G

    1989-11-01

    The term of swimming pool hydraulics means the process of letting in and drawing off water to and from the pool while ensuring that no inadmissible water-borne contaminant concentrations will occur anywhere within the pool. Measurements were performed on a pool to study the significance of correct pool hydraulics. The author points out that a wrong water recirculation design will bring to nought the effects of an elaborate water treatment system; by contrast, poor pool water quality can be greatly improved by redesigning the pool water hydraulics approach. In principle, systems with with water inlet at one side and water outlet at the far side will fall short of hygienic requirements. (BWI).

  9. Studies of thermal stratification in water pool

    International Nuclear Information System (INIS)

    Verma, P.K.; Chandraker, D.K.; Nayak, A.K.; Vijayan, P.K.

    2015-01-01

    Large water pools are used as a heat sink for various cooling systems used in industry. In context of advance nuclear reactors like AHWR, it is used as ultimate heat sink for passive systems for decay heat removal and containment cooling. This system incorporates heat exchangers submerged in the large water pool. However, heat transfer by natural convection in pool poses a problem of thermal stratification. Due to thermal stratification hot layers of water accumulate over the relatively cold one. The heat transfer performance of heat exchanger gets deteriorated as a hot fluid envelops it. In the nuclear reactors, the walls of the pool are made of concrete and it may subject to high temperature due to thermal stratification which is not desirable. In this paper, a concept of employing shrouds around the heat source is studied. These shrouds provide a bulk flow in the water pool, thereby facilitating mixing of hot and cold fluid, which eliminate stratification. The concept has been applied to the a scaled model of Gravity Driven Water Pool (GDWP) of AHWR in which Isolation Condensers (IC) tubes are submerged for decay heat removal of AHWR using ICS and thermal stratification phenomenon was predicted with and without shrouds. To demonstrate the adequacy of the effectiveness of shroud arrangement and to validate the simulation methodology of RELAP5/Mod3.2, experiments has been conducted on a scaled model of the pool with and without shroud. (author)

  10. Spent fuel pool cleanup and stabilization

    International Nuclear Information System (INIS)

    Miller, R.L.

    1987-06-01

    Each of the plutonium production reactors at Hanford had a large water-filled spent fuel pool to provide interim storage of irradiated fuel while awaiting shipment to the separation facilities. After cessation of reactor operations the fuel was removed from the pools and the water levels were drawn down to a 5- to 10-foot depth. The pools were maintained with the water to provide shielding and radiological control. What appeared to be a straightforward project to process the water, remove the sediments from the basin, and stabilize the contamination on the floors and walls became a very complex and time consuming operation. The sediment characteristics varied from pool to pool, the ion exchange system required modification, areas of hard-pack sediments were discovered on the floors, special arrangements to handle and package high dose rate items for shipment were required, and contract problems ensued with the subcontractor. The original schedule to complete the project from preliminary engineering to final stabilization of the pools was 15 months. The actual time required was about 25 months. The original cost estimate to perform the work was $2,651,000. The actual cost of the project was $5,120,000, which included $150,000 for payment of claims to the subcontractor. This paper summarizes the experiences associated with the cleanup and radiological stabilization of the 100-B, -C, -D, and -DR spent fuel pools, and discusses a number of lessons learned items

  11. Distributed Technologies in a Data Pool

    Science.gov (United States)

    Keiser, K.; Conover, H.; Graves, S.; He, Y.; Regner, K.; Smith, M.

    2004-12-01

    A Data Pool is an on-line repository providing interactive and programmatic access to data products through a variety of services. The University of Alabama in Huntsville has developed and deployed such a Data Pool in conjunction with the DISCOVER project, a collaboration with NASA and Remote Sensing Systems. DISCOVER provides long-term ocean and climate data from a variety of passive microwave satellite instruments, including such products as sea-surface temperature and wind, air temperature, atmospheric water vapor, cloud water and rain rate. The Data Pool provides multiple methods to access and visualize these products, including conventional HTTP and FTP access, as well as data services that provide for enhanced usability and interoperability, such as GridFTP, OPeNDAP, OpenGIS-compliant web mapping and coverage services, and custom subsetting and packaging services. This paper will focus on the distributed service technologies used in the Data Pool, which spans heterogeneous machines at multiple locations. For example, in order to provide seamless access to data at multiple sites, the Data Pool provides catalog services for all data products at the various data server locations. Under development is an automated metadata generation tool that crawls the online data repositories regularly to dynamically update the Data Pool catalog with information about newly generated data files. For efficient handling of data orders across distributed repositories, the Data Pool also implements distributed data processing services on the file servers where the data resides. Ontologies are planned to support automated service chaining for custom user requests. The UAH Data Pool is based on a configurable technology framework that integrates distributed data services with a web interface and a set of centralized database services for catalogs and order tracking. While this instantiation of the Data Pool was implemented to meet the needs of the DISCOVER project, the framework was

  12. A Pool of Distant Galaxies

    Science.gov (United States)

    2008-11-01

    Anyone who has wondered what it might be like to dive into a pool of millions of distant galaxies of different shapes and colours, will enjoy the latest image released by ESO. Obtained in part with the Very Large Telescope, the image is the deepest ground-based U-band image of the Universe ever obtained. It contains more than 27 million pixels and is the result of 55 hours of observations with the VIMOS instrument. A Sea of Galaxies ESO PR Photo 39/08 A Pool of Distant Galaxies This uniquely beautiful patchwork image, with its myriad of brightly coloured galaxies, shows the Chandra Deep Field South (CDF-S), arguably the most observed and best studied region in the entire sky. The CDF-S is one of the two regions selected as part of the Great Observatories Origins Deep Survey (GOODS), an effort of the worldwide astronomical community that unites the deepest observations from ground- and space-based facilities at all wavelengths from X-ray to radio. Its primary purpose is to provide astronomers with the most sensitive census of the distant Universe to assist in their study of the formation and evolution of galaxies. The new image released by ESO combines data obtained with the VIMOS instrument in the U- and R-bands, as well as data obtained in the B-band with the Wide-Field Imager (WFI) attached to the 2.2 m MPG/ESO telescope at La Silla, in the framework of the GABODS survey. The newly released U-band image - the result of 40 hours of staring at the same region of the sky and just made ready by the GOODS team - is the deepest image ever taken from the ground in this wavelength domain. At these depths, the sky is almost completely covered by galaxies, each one, like our own galaxy, the Milky Way, home of hundreds of billions of stars. Galaxies were detected that are a billion times fainter than the unaided eye can see and over a range of colours not directly observable by the eye. This deep image has been essential to the discovery of a large number of new galaxies

  13. Modal analysis of pool door in water tank

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Soo; Jeong, Kyeong Hoon; Park, Chan Gook; Koo, In Soo [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    A pool door is installed at the chase of the pool gate by means of an overhead crane in the building of a research reactor. The principal function of the pool door, which is located between the reactor pool and service pool, is to separate the reactor pool from the service pool for the maintenance and/or the removal of the equipment either in the reactor pool or service pool. The pool door consists of stainless steel plates supported by structural steel frames and sealing components. The pool door is equipped with double inflatable gaskets. The configuration of the pool door is shown in Figure 1. The FEM analysis and theoretical calculation by the formula were performed to evaluate the natural frequency for the pool door in the water. The results from the two methods were compared.

  14. The Role of Nuclear Insurance Pools

    International Nuclear Information System (INIS)

    Reitsma, S. M. S.

    2006-01-01

    Since fifty years insurers respond to the need of both governments and the electricity industry to provide financial protection to cover the perils presented by the use of nuclear energy for peaceful purposes. This paper aims at explaining what difficulties had to be solved in order to enable insurers to provide such protection, that as a solution to these difficulties Nuclear Insurance Pools were formed, how such pools operate and what security they provide. Thereby not only a number of universal principles underlying nuclear pool insurance will be explained, but also some differences in the characteristics of such insurance per group of countries. (author)

  15. Laser surveillance systems for fuel storage pools

    International Nuclear Information System (INIS)

    Boeck, H.

    1985-06-01

    A Laser Surveillance System (LASSY) as a new safeguards device has been developed under the IAEA research contract No. 3458/RB at the Atominstitut Wien using earlier results by S. Fiarman. This system is designed to act as a sheet of light covering spent fuel assemblies in spent fuel storage pools. When movement of assemblies takes place, LASSY detects and locates the position of the movement in the pool and when interrogated, presents a list of pool positions and times of movement to the safeguards inspector. A complete prototype system was developed and built. Full scale tests showed the principal working capabilities of a LASSY underwater

  16. 10 CFR 36.63 - Pool water purity.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water...

  17. The Nuclear Insurance Pools: Operations and Covers

    International Nuclear Information System (INIS)

    Tetley, M.

    2008-01-01

    Nuclear insurance pools have provided insurance for the nuclear industry for over fifty years and it is fair to say that the development of civil nuclear power would not have been possible without the support of the commercial insurance market. The unknown risks presented by the nascent nuclear power industry in the 1950s required a leap of faith by insurers who developed specialist pooled insurance capacity to ensure adequate capacity to back up the operators' compensation obligations. Since then, nuclear insurance pools have evolved to become comprehensive suppliers of most types of insurance for nuclear plant globally. This paper will outline the structure, development, products and current operations of nuclear insurance pools.(author)

  18. Ingestion of swimming pool water by recreational

    Data.gov (United States)

    U.S. Environmental Protection Agency — Swimming pool water ingestion data. This dataset is associated with the following publication: Dufour, A., L. Wymer, M. Magnuson, T. Behymer, and R. Cantu. Ingestion...

  19. Nuclear Insurance Pools: Worldwide Practice and Development

    International Nuclear Information System (INIS)

    Reitsma, S. M. S.

    1998-01-01

    The development of nuclear installations to produce electricity led to the establishment of Nuclear Insurance Pools and the introduction of international Conventions on Third Party Liability. Nuclear Pools offer both Third Party Liability insurance, reflecting the Conventions' principles, and other insurance products. They are market-wide, providing a facility for participation by insurers who could not otherwise write the insurance for the particularly sensitive nuclear risk. All acceptances are for the net retention of each Member without recourse to individual reinsurance protection. Common account reinsurance is arranged with other Nuclear Pools all over the world. Thus, a transparency is created, which ensures the highest degree of reinsurance security and imposes a known finite limit to each participating insurer's commitment. Therefore, Pool-members are prepared to make a greater commitment to nuclear risks than would be case where they felt uncertain as regards their total exposure following a significant loss. (author)

  20. AE/VCE Unconfirmed Vernal Pools

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

  1. AE/VCE Confirmed Vernal Pools

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

  2. Investigations in Marine Chemistry: Tide Pool Ecology.

    Science.gov (United States)

    Schlenker, Richard M.

    Students investigated the salinity of tide pools at different levels in the intertidal zone. Data are analyzed collectively. Students graphed and discussed data. Included are suggestions for evaluation and further study. (Author)

  3. 7 CFR 1126.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... excluded from the supply plant's shipments in computing the plant's shipping percentage. (d) A plant... part, or the plant has automatic pooling status under the other Federal order; and (7) That portion of...

  4. 7 CFR 1001.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... excluded from the supply plant's shipments in computing the percentages in paragraphs (c)(1) and (2) of... plant has automatic pooling status under the other Federal order. [64 FR 47954, Sept. 1, 1999, as...

  5. 7 CFR 1007.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ...-upon use other than Class I shall be excluded from the supply plant's shipments in computing the plant... under the order in this part, or such plant has automatic pooling status under such other order. (h) Any...

  6. Microbial quality of a marine tidal pool

    CSIR Research Space (South Africa)

    Genthe, Bettina

    1995-01-01

    Full Text Available In this study the source of microbial pollution to a tidal pool was investigated. Both adjacent seawater which could contribute to possible faecal pollution and potential direct bather pollution were studied. The microbial quality of the marine...

  7. Robotic cleaning of a spent fuel pool

    International Nuclear Information System (INIS)

    Roman, H.T.; Marian, F.A.; Silverman, E.B.; Barkley, V.P.

    1987-01-01

    Spent fuel pools at nuclear power plants are not cleaned routinely, other than by purifying the water that they contain. Yet, debris can collect on the bottom of a pool and should be removed prior to fuel transfer. At Public Service Electric and Gas Company's Hope Creek Nuclear Power Plant, a submersible mobile robot - ARD Corporation's SCAVENGER - was used to clean the bottom of the spent fuel pool prior to initial fuel loading. The robotic device was operated remotely (as opposed to autonomously) with a simple forward/reverse control, and it cleaned 70-80% of the pool bottom. This paper reports that a simple cost-benefit analysis shows that the robotic device would be less expensive, on a per mission basis, than other cleaning alternatives, especially if it were used for other similar cleaning operations throughout the plant

  8. Pooling strategies for St Petersburg gamblers

    OpenAIRE

    Csörgö, Sandor; Simons, Gordon

    2006-01-01

    Peter offers to play exactly one St Petersburg game with each of [math] players, Paul [math] , [math] , Paul [math] , whose conceivable pooling strategies are described by all possible probability distributions [math] . Comparing infinite expectations, we characterize among all [math] those admissible strategies for which the pooled winnings, each distributed as [math] , yield a finite added value for each and every one of Paul [math] , [math] , Paul [math] in comparison with their individual...

  9. Welding pool measurement using thermal array sensor

    Science.gov (United States)

    Cho, Chia-Hung; Hsieh, Yi-Chen; Chen, Hsin-Yi

    2015-08-01

    Selective laser melting (SLM) is an additive manufacturing (AM) technology that uses a high-power laser beam to melt metal powder in chamber of inert gas. The process starts by slicing the 3D CAD data as a digital information source into layers to create a 2D image of each layer. Melting pool was formed by using laser irradiation on metal powders which then solidified to consolidated structure. In a selective laser melting process, the variation of melt pool affects the yield of a printed three-dimensional product. For three dimensional parts, the border conditions of the conductive heat transport have a very large influence on the melt pool dimensions. Therefore, melting pool is an important behavior that affects the final quality of the 3D object. To meet the temperature and geometry of the melting pool for monitoring in additive manufacturing technology. In this paper, we proposed the temperature sensing system which is composed of infrared photodiode, high speed camera, band-pass filter, dichroic beam splitter and focus lens. Since the infrared photodiode and high speed camera look at the process through the 2D galvanometer scanner and f-theta lens, the temperature sensing system can be used to observe the melting pool at any time, regardless of the movement of the laser spot. In order to obtain a wide temperature detecting range, 500 °C to 2500 °C, the radiation from the melting pool to be measured is filtered into a plurality of radiation portions, and since the intensity ratio distribution of the radiation portions is calculated by using black-body radiation. The experimental result shows that the system is suitable for melting pool to measure temperature.

  10. Numerical modelling of methanol liquid pool fires

    Science.gov (United States)

    Prasad, Kuldeep; Li, Chiping; Kailasanath, K.; Ndubizu, Chuka; Ananth, Ramagopal; Tatem, P. A.

    1999-12-01

    The focus of this paper is on numerical modelling of methanol liquid pool fires. A mathematical model is first developed to describe the evaporation and burning of a two-dimensional or axisymmetric pool containing pure liquid methanol. Then, the complete set of unsteady, compressible Navier-Stokes equations for reactive flows are solved in the gas phase to describe the convection of the fuel gases away from the pool surface, diffusion of the gases into the surrounding air and the oxidation of the fuel into product species. Heat transfer into the liquid pool and the metal container through conduction, convection and radiation are modelled by solving a modified form of the energy equation. Clausius-Clapeyron relationships are invoked to model the evaporation rate of a two-dimensional pool of pure liquid methanol. The governing equations along with appropriate boundary and interface conditions are solved using the flux-corrected transport algorithm. Numerical results exhibit a flame structure that compares well with experimental observations. Temperature profiles and burning rates were found to compare favourably with experimental data from single- and three-compartment laboratory burners. The model predicts a puffing frequency of approximately 12 Hz for a 1 cm diameter methanol pool in the absence of any air co-flow. It is also observed that increasing the air co-flow velocity helps in stabilizing the diffusion flame, by pushing the vortical structures away from the flame region.

  11. Recent advances in probabilistic species pool delineations

    Directory of Open Access Journals (Sweden)

    Dirk Nikolaus Karger

    2016-07-01

    Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

  12. Donating Blood

    Science.gov (United States)

    ... The medical history includes questions that help blood bank staff decide if a person is healthy enough to donate blood. They'll ... Food and Drug Administration (FDA) regulates U.S. blood banks. All blood ... operating. Sometimes people who donate blood notice a few minor side ...

  13. What's Blood?

    Science.gov (United States)

    ... Body Make Blood? It's not made in a kitchen, but blood has ingredients, just like a recipe. ... these ingredients together and you have blood — an essential part of the circulatory system. Thanks to your ...

  14. Blood typing

    Science.gov (United States)

    ... detect these minor antigens. It is done before transfusions, except in emergency situations. Alternative Names Cross matching; Rh typing; ABO blood typing; Blood group; Anemia - immune hemolytic blood type; ...

  15. Blood smear

    Science.gov (United States)

    ... smear URL of this page: //medlineplus.gov/ency/article/003665.htm Blood smear To use the sharing features on this ... view of cellular parasites Malaria, photomicrograph of cellular parasites Red blood cells, sickle cells Red blood cells, sickle and ...

  16. Parvovirus B19 viraemia in Dutch blood donors

    NARCIS (Netherlands)

    Zaaijer, H. L.; Koppelman, M. H. G. M.; Farrington, C. P.

    2004-01-01

    Blood, donated by asymptomatic donors, may contain and transmit parvovirus B19. To investigate the dynamics of parvovirus viraemia in asymptomatic blood donors, we studied the amounts of parvovirus DNA in pools of donor plasma, the prevalence of parvovirus antibodies among blood donors in relation

  17. Blood Culture (For Parents)

    Science.gov (United States)

    ... Metabolic Panel (BMP) Blood Test: Complete Blood Count Basic Blood Chemistry Tests Getting a Blood Test (Video) Blood Test: Basic Metabolic Panel Blood Test: Comprehensive Metabolic Panel Blood ...

  18. Self-formed waterfall plunge pools in homogeneous rock

    Science.gov (United States)

    Scheingross, Joel S.; Lo, Daniel Y.; Lamb, Michael P.

    2017-01-01

    Waterfalls are ubiquitous, and their upstream propagation can set the pace of landscape evolution, yet no experimental studies have examined waterfall plunge pool erosion in homogeneous rock. We performed laboratory experiments, using synthetic foam as a bedrock simulant, to produce self-formed waterfall plunge pools via particle impact abrasion. Plunge pool vertical incision exceeded lateral erosion by approximately tenfold until pools deepened to the point that the supplied sediment could not be evacuated and deposition armored the pool bedrock floor. Lateral erosion of plunge pool sidewalls continued after sediment deposition, but primarily at the downstream pool wall, which might lead to undermining of the plunge pool lip, sediment evacuation, and continued vertical pool floor incision in natural streams. Undercutting of the upstream pool wall was absent, and our results suggest that vertical drilling of successive plunge pools is a more efficient waterfall retreat mechanism than the classic model of headwall undercutting and collapse in homogeneous rock.

  19. Structure of pool in reactor building

    International Nuclear Information System (INIS)

    Yokoyama, Shigeki.

    1997-01-01

    Shielding walls made of iron-reinforced concrete having a metal liner including two body walls rigidly combined to the upper surface of a reactor container are disposed at least to one of an equipment pool or spent fuel storage pool in a reactor building. A rack for temporarily placing an upper lattice plate is detachably attached at least above one of a steam dryer or a gas/liquid separator temporarily placed in the temporary pool, and the height from the bottom portion to the upper end of the shielding wall is determined based on the height of an upper lattice plate temporary placed on the rack and the water depth required for shielding radiation from the upper lattice plate. An operator's exposure on the operation floor can be reduced by the shielding wall, and radiation dose from the spent fuels is reduced. The increase of the height of a pool guarder enhances bending resistance as a ceiling. In addition, the total height of them is made identical with the depth of the spent fuel storage pool thereby enabling to increase storage area for spent fuels. (N.H.)

  20. Cooling device for reactor suppression pool

    International Nuclear Information System (INIS)

    Togasaki, Susumu; Kato, Kiyoshi.

    1994-01-01

    In a cooling device of a reactor suppression pool, when a temperature of pool water is abnormally increased and a heat absorbing portion is heated by, for example, occurrence of an accident, coolants are sent to the outside of the reactor container to actuates a thermally operating portion by the heat energy of coolants and drive heat exchanging fluids of a secondary cooling system. If the heat exchanging fluids are sent to a cooling portion, the coolants are cooled and returned to the heat absorbing portion of the suppression pool water. If the heat absorbing portion is heat pipes, the coolants are evaporated by heat absorbed from the suppression pool water, steams are sent to the thermally operating portion, then coolants are liquefied and caused to return to the heat absorbing portion. If the thermal operation portion is a gas turbine, the gas turbine is operated by the coolants, and it is converted to a rotational force to drive heat exchanging fluids by pumps. By constituting the cooling portion with a condensator, the coolants are condensed and liquefied and returned to the heat absorbing portion of the suppression pool water. (N.H.)

  1. Condensation in a two-phase pool

    International Nuclear Information System (INIS)

    Duffey, R.B.; Hughes, E.D.

    1991-01-01

    We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine some limits in ideal cases

  2. Genomic analyses of tropical beef cattle fertility based on genotyping pools of Brahman cows with unknown pedigree.

    Science.gov (United States)

    Reverter, A; Porto-Neto, L R; Fortes, M R S; McCulloch, R; Lyons, R E; Moore, S; Nicol, D; Henshall, J; Lehnert, S A

    2016-10-01

    We introduce an innovative approach to lowering the overall cost of obtaining genomic EBV (GEBV) and encourage their use in commercial extensive herds of Brahman beef cattle. In our approach, the DNA genotyping of cow herds from 2 independent properties was performed using a high-density bovine SNP chip on DNA from pooled blood samples, grouped according to the result of a pregnancy test following their first and second joining opportunities. For the DNA pooling strategy, 15 to 28 blood samples from the same phenotype and contemporary group were allocated to pools. Across the 2 properties, a total of 183 pools were created representing 4,164 cows. In addition, blood samples from 309 bulls from the same properties were also taken. After genotyping and quality control, 74,584 remaining SNP were used for analyses. Pools and individual DNA samples were related by means of a "hybrid" genomic relationship matrix. The pooled genotyping analysis of 2 large and independent commercial populations of tropical beef cattle was able to recover significant and plausible associations between SNP and pregnancy test outcome. We discuss 24 SNP with significant association ( < 1.0 × 10) and mapped within 40 kb of an annotated gene. We have established a method to estimate the GEBV in young herd bulls for a trait that is currently unable to be predicted at all. In summary, our novel approach allowed us to conduct genomic analyses of fertility in 2 large commercial Brahman herds managed under extensive pastoral conditions.

  3. Radiolabelled blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Lavender, J.P.

    1986-12-01

    After the introduction of gamma-emitting labels for blood-cells the use of radio-labelled blood cells is not only limited to kinetics of blood cells but it is also possible to localise inflammations, abscesses and thrombus. The most commonly applied label for red cells is Tc-99m. The most widely used technique for labelling granulocytes or platelets is In-111-oxine. In future the labelling of blood cells will be more simple and more specific due to monoclonal antibodies onto the platelet or the granulocyte cell surface. Labelled red cells have their main application in blood-pool imaging and in localisation of gastrointestinal bleeding. Besides the determination of the platelet life-span in haematologic disorders labelled platelets allow to localise thrombus and to show abnormal vasculature in the rejecting kidney. The commonest application for In-111-oxin labelled granulocytes is to show abdominal inflammations to localise inflamed bowel segments and to assess the inflammatory activity in chronic inflammatory bowel diseases. Moreover brain abscesses, bone sepsis and lung sepsis can be identified.

  4. 13 CFR 120.1706 - Pool Originator's retained interest in Pool.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pool Originator's retained interest in Pool. 120.1706 Section 120.1706 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan...

  5. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    spreading of pathogens between swimmers because of its residual disinfection effect. In addition to potential contamination of pathogenic microorganisms, swimming pool water is polluted by organic matter deposited from the bathers such as saliva, urine, sweat, hair and personal care products. Since chlorine...... is a strong oxidant it oxidizes the organic matter in the pool water and forms disinfection byproducts (DBPs). More than 100 different DBPs have been identified. Some of these have been found to be genotoxic and may pose an increased cancer risk for the bathers. The aim of this thesis was to give an overview...... of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

  6. Simulation of pool scrubbing experiments using BUSCA

    International Nuclear Information System (INIS)

    Dehbi, A.; Guentay, S.

    1994-01-01

    BUSCA-PSI is a computer code which predicts the aerosol scrubbing taking place when gas bubbles containing fission products rise through stagnant pools of water after a postulated severe accident. A Lagrangian formulation is adopted to follow the path of a bubble as it rises toward the surface of the pool. The BUSCA model includes most aerosol removal mechanisms which are thought to be significant, namely: Jet Impaction at tile orifice, Convection/Diffusiophoresis during steam condensation, Thermophoresis, Sedimentation, Centrifugal Impaction during bubble rise, and Brownian Diffusion. The hydraulic modelling offers a variety of options for the initial globule volume, the stable bubble size, tile bubble rise velocity, and the bubble shape. The heat and mass transfer part of tile model uses correlations found in the relevant literature. BUSCA simulations were performed to determine the decontamination factor (DF) dependence on key aerosol and thermal hydraulic parameters. The decontamination factor increases with height, pool temperature subcooling, and steam content. The decontamination factor exhibits a parabolic dependence on the particle radius. At low particle sizes, the DF is high due to Brownian Diffusion which is the dominant removal mechanism. The DF hits a minimum and then increases with particle size as Centrifugal Impaction and Sedimentation become important. In separate calculations, BUSCA was used to the simulate the aerosol scrubbing experiments performed by EPRI. For cold pool tests, the predicted scrubbing efficiencies were in a good, conservative agreement with the data for both Tin and CsI, and the discrepancies were within the reported measurement errors. For hot pool tests, the code systematically underpredicted the scrubbing DF's; this is potentially due to condensation in the gas space above the pool, a situation not currently modelled by BUSCA. The code was also tested against data produced by the Tepco-Toshiba-Hitachi experiments. The

  7. Zooplankton at deep Red Sea brine pools

    KAUST Repository

    Kaartvedt, Stein

    2016-03-02

    The deep-sea anoxic brines of the Red Sea comprise unique, complex and extreme habitats. These environments are too harsh for metazoans, while the brine–seawater interface harbors dense microbial populations. We investigated the adjacent pelagic fauna at two brine pools using net tows, video records from a remotely operated vehicle and submerged echosounders. Waters just above the brine pool of Atlantis II Deep (2000 m depth) appeared depleted of macrofauna. In contrast, the fauna appeared to be enriched at the Kebrit Deep brine–seawater interface (1466 m).

  8. One component, volume heated, boiling pool thermohydraulics

    International Nuclear Information System (INIS)

    Bede, M.; Perret, C.; Pretrel, H.; Seiler, J.M.

    1993-01-01

    Prior work on boiling pools provided heat exchange correlations valid for bubbly flow with laminar or turbulent boundary layers. New experiments performed with water (SEBULON) and UO 2 (SCARABEE BF2) in a churn-turbulent flow configuration show unexpected heat flux distributions for which the maximum heat flux may be situated well below the pool surface. The origin of this behaviour is attributed to condensation effects, very unstable boundary layer flow and surface oscillation. A calculation model is discussed which permits to approach the experimental heat flux distribution with reasonable accuracy. (authors). 7 figs., 2 appendix., 14 refs

  9. Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

    International Nuclear Information System (INIS)

    Sathiah, Pratap; Roelofs, Ferry

    2014-01-01

    Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor

  10. Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

    Energy Technology Data Exchange (ETDEWEB)

    Sathiah, Pratap, E-mail: pratap.sathiah78@gmail.com [Shell Global Solutions Ltd., Brabazon House, Concord Business Park, Threapwood Road, Manchester M220RR (United Kingdom); Roelofs, Ferry, E-mail: roelofs@nrg.eu [Nuclear Research and Consultancy Group (NRG), Westerduinweg 3, 1755ZG Petten (Netherlands)

    2014-10-15

    Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor.

  11. 13 CFR 120.1705 - Pool formation requirements.

    Science.gov (United States)

    2010-01-01

    ... requirements. SBA may adjust the Pool characteristics periodically based on program experience and market... a Pool involving a Pool Loan it does not own, it must purchase the Loan Interest it proposes to pool... purchase the Loan Interest and take it into inventory or settle the purchase of the Loan Interest through...

  12. Delineating probabilistic species pools in ecology and biogeography

    OpenAIRE

    Karger, Dirk Nikolaus; Cord, Anna F; Kessler, Michael; Kreft, Holger; Kühn, Ingolf; Pompe, Sven; Sandel, Brody; Sarmento Cabral, Juliano; Smith, Adam B; Svenning, Jens-Christian; Tuomisto, Hanna; Weigelt, Patrick; Wesche, Karsten

    2016-01-01

    Aim To provide a mechanistic and probabilistic framework for defining the species pool based on species-specific probabilities of dispersal, environmental suitability and biotic interactions within a specific temporal extent, and to show how probabilistic species pools can help disentangle the geographical structure of different community assembly processes. Innovation Probabilistic species pools provide an improved species pool definition based on probabilities in conjuncti...

  13. A strategy for optimizing item-pool management

    NARCIS (Netherlands)

    Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

    2006-01-01

    Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

  14. Public Swimming Pools | Florida Department of Health

    Science.gov (United States)

    Illness Disease Reporting and Surveillance Bureau of Public Health Laboratories Environmental Health Air Air Monitoring Carbon Monoxide Indoor Air Quality Mold Radon Water Aquatic Toxins Beach Water Quality purification, testing, treatment, and disinfection procedures. To ensure that the pool technicians are

  15. 28 CFR 540.64 - Press pools.

    Science.gov (United States)

    2010-07-01

    ... Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT CONTACT WITH PERSONS IN THE COMMUNITY Contact With News Media § 540.64 Press pools. (a) The Warden may establish a... shall notify all news media representatives who have requested interviews or visits that have not been...

  16. Stein's neuronal model with pooled renewal input

    Czech Academy of Sciences Publication Activity Database

    Rajdl, K.; Lánský, Petr

    2015-01-01

    Roč. 109, č. 3 (2015), s. 389-399 ISSN 0340-1200 Institutional support: RVO:67985823 Keywords : Stein’s model * Poisson process * pooled renewal processes * first-passage time Subject RIV: BA - General Mathematics Impact factor: 1.611, year: 2015

  17. Swimming-pool piles; Piles piscines

    Energy Technology Data Exchange (ETDEWEB)

    Trioulaire, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10{sup 13}. This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [French] En France, deux piles piscines, Melusine et Triton, viennent d'entrer en service. La pile piscine est l'outil de recherche ideal pour des flux de neutrons de l'ordre de 10{sup 13}. Ce type de pile peut interesser des maintenant de nombreux centres de recherches mais il faut reduire son prix de revient et rompre avec le conformisme de sa conception. Il y a avantage: - a enterrer la piscine; - a supprimer les canaux experimentaux; - a concentrer le circuit de refrigeration dans la piscine; - a effectuer toutes les manipulations dans l'eau; - a doubler le coeur. (auteur)

  18. Spectrum pooling in MnWave Networks

    DEFF Research Database (Denmark)

    Boccardi, Federico; Shokri-Ghadikolaei, Hossein; Fodor, Gabor

    2016-01-01

    Motivated by the specific characteristics of mmWave technologies, we discuss the possibility of an authorization regime that allows spectrum sharing between multiple operators, also referred to as spectrum pooling. In particular, considering user rate as the performance measure, we assess...

  19. Pooling Objects for Recognizing Scenes without Examples

    NARCIS (Netherlands)

    Kordumova, S.; Mensink, T.; Snoek, C.G.M.

    2016-01-01

    In this paper we aim to recognize scenes in images without using any scene images as training data. Different from attribute based approaches, we do not carefully select the training classes to match the unseen scene classes. Instead, we propose a pooling over ten thousand of off-the-shelf object

  20. The new pooled cohort equations risk calculator

    DEFF Research Database (Denmark)

    Preiss, David; Kristensen, Søren L

    2015-01-01

    disease and any measure of social deprivation. An early criticism of the Pooled Cohort Equations Risk Calculator has been its alleged overestimation of ASCVD risk which, if confirmed in the general population, is likely to result in statin therapy being prescribed to many individuals at lower risk than...

  1. DNA pooling strategies for categorical (ordinal) traits

    Science.gov (United States)

    Despite reduced genotyping costs in recent years, obtaining genotypes for all individuals in a population may still not be feasible when sample size is large. DNA pooling provides a useful alternative to determining genotype effects. Clustering algorithms allow for grouping of individuals (observati...

  2. Pooling ASR data for closely related languages

    CSIR Research Space (South Africa)

    Van Heerden, C

    2010-05-01

    Full Text Available We describe several experiments that were conducted to assess the viability of data pooling as a means to improve speech-recognition performance for under-resourced languages. Two groups of closely related languages from the Southern Bantu language...

  3. "Teisele poole" Agambeniga ja Agambenita / Ragne Nukk

    Index Scriptorium Estoniae

    Nukk, Ragne, 1984-

    2012-01-01

    Tallinna Fotokuu rahvusvahelise fotonäituse "Teisele poole" ideeliste lähtekohtade tõlgendamisest. Autor kõrvutab Adam Budaki kuraatornäituse aluseks olnud Giorgio Agambeni esseed „Viimne kohtupäev“ näitusel eksponeeritud piltidega

  4. 7 CFR 1033.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... association and it fulfills the following conditions: (1) The aggregate monthly quantity supplied by all... or aseptically-processed fluid milk products. (c) A supply plant from which the quantity of bulk... operator of a supply plant located within the marketing area may include deliveries to pool distributing...

  5. Benthic assemblages of rock pools in northern Portugal: seasonal and between-pool variability

    Directory of Open Access Journals (Sweden)

    Iacopo Bertocci

    2012-11-01

    Full Text Available We investigated the seasonal (winter vs summer and within season and spatial (between-pool variability of benthic assemblages of rock pools at mid-intertidal level along the shore of Viana do Castelo (North Portugal. Physical traits of rock pools, including size, depth and position along the shore, were also compared between pools. While pools did not differ for any of the examined physical traits, results indicated a clear seasonal difference in the structure of assemblages, including a total of 49 macroalgal and 13 animal taxa. This finding was driven by six taxa that are more abundant in winter (the reef-forming polychaete Sabellaria alveolata, the articulated coralline algae Corallina spp., the brown alga Bifurcaria bifurcata, the encrusting coralline alga Lithophyllum incrustans, the red alga Chondracanthus acicularis and the grazing snails Gibbula spp. and four algal taxa that are more abundant in summer (the invasive brown Sargassum muticum, the green Ulva spp., the kelp Laminaria ochroleuca and the filamentous red Ceramium spp.. These data provide a new contribution to the knowledge of rock pool systems and have potential implications for monitoring programmes aimed at assessing ecological modifications related to natural and anthropogenic disturbances and for identifying processes responsible for the variability of rock pool assemblages.

  6. Generalizing Pooling Functions in CNNs: Mixed, Gated, and Tree.

    Science.gov (United States)

    Lee, Chen-Yu; Gallagher, Patrick; Tu, Zhuowen

    2018-04-01

    In this paper, we seek to improve deep neural networks by generalizing the pooling operations that play a central role in the current architectures. We pursue a careful exploration of approaches to allow pooling to learn and to adapt to complex and variable patterns. The two primary directions lie in: (1) learning a pooling function via (two strategies of) combining of max and average pooling, and (2) learning a pooling function in the form of a tree-structured fusion of pooling filters that are themselves learned. In our experiments every generalized pooling operation we explore improves performance when used in place of average or max pooling. We experimentally demonstrate that the proposed pooling operations provide a boost in invariance properties relative to conventional pooling and set the state of the art on several widely adopted benchmark datasets. These benefits come with only a light increase in computational overhead during training (ranging from additional 5 to 15 percent in time complexity) and a very modest increase in the number of model parameters (e.g., additional 1, 9, and 27 parameters for mixed, gated, and 2-level tree pooling operators, respectively). To gain more insights about our proposed pooling methods, we also visualize the learned pooling masks and the embeddings of the internal feature responses for different pooling operations. Our proposed pooling operations are easy to implement and can be applied within various deep neural network architectures.

  7. Corium quench in deep pool mixing experiments

    International Nuclear Information System (INIS)

    Spencer, B.W.; McUmber, L.; Gregorash, D.; Aeschlimann, R.; Sienicki, J.J.

    1985-01-01

    The results of two recent corium-water thermal interaction (CWTI) tests are described in which a stream of molten corium was poured into a deep pool of water in order to determine the mixing behavior, the corium-to-water heat transfer rates, and the characteristic sizes of the quenched debris. The corium composition was 60% UO 2 , 16% ZrO 2 , and 24% stainless steel by weight; its initial temperature was 3080 K, approx.160 K above the oxide phase liquidus temperature. The corium pour stream was a single-phase 2.2 cm dia liquid column which entered the water pool in film boiling at approx.4 m/s. The water subcooling was 6 and 75C in the two tests. Test results showed that with low subcooling, rapid steam generation caused the pool to boil up into a high void fraction regime. In contrast, with large subcooling no net steam generation occurred, and the pool remained relatively quiescent. Breakup of the jet appeared to occur by surface stripping. In neither test was the breakup complete during transit through the 32 cm deep water pool, and molten corium channeled to the base where it formed a melt layer. The characteristic heat transfer rates measured 3.5 MJ/s and 2.7 MJ/s during the fall stage for small and large subcooling, respectively; during the initial stage of bed quench, the surface heat fluxes measured 2.4 MW/m 2 and 3.7 MW/m 2 , respectively. A small mass of particles was formed in each test, measuring typically 0.1 to 1 mm and 1 to 5 mm dia for the large and small subcooling conditions, respectively. 9 refs., 13 figs., 1 tab

  8. Suncatcher and cool pool. Project report

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, J.

    1981-03-01

    The Suncatcher is a simple, conical solar concentrating device that captures light entering clerestory windows and directs it onto thermal storage elements at the back of a south facing living space. The cone shape and inclination are designed to capture low angle winter sunlight and to reflect away higher angle summer sunlight. It is found that winter radiation through a Suncatcher window is 40 to 50% higher than through an ordinary window, and that the average solar fraction is 59%. Water-filled steal culvert pipes used for thermal storage are found to undergo less stratification, and thus to be more effective, when located where sunlight strikes the bottom rather than the top. Five Suncatcher buildings are described. Designs are considered for 32/sup 0/, 40/sup 0/ and 48/sup 0/ north latitude, and as the latitude increases, the inclination angle of the cone should be lowered. The Cool Pool is an evaporating, shaded roof pond which thermosiphons cool water into water-filled columns within a building. Preliminary experiments indicate that the best shade design has unimpeded north sky view, good ventilation, complete summer shading, a low architectural profile, and low cost attic vent lowers work. Another series of experiments established the satisfactory performance of the Cool Pool on a test building using four water-filled cylinders, two cylinders, and two cylinders connected to the Cool Pool through a heat exchanger. Although an unshaded pool cools better at night than a shaded one, daytime heat gain far offsets this advantage. A vinyl waterbag heat exchanger was developed for use with the Cool Pool. (LEW)

  9. Pathogen reduction of blood components.

    Science.gov (United States)

    Solheim, Bjarte G

    2008-08-01

    Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by