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Sökning: L773:0278 4297 OR L773:1550 9613

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1.
  • Eisenbrey, John R., et al. (författare)
  • Parametric Subharmonic Imaging Using a Commercial Intravascular Ultrasound Scanner : An In Vivo Feasibility Study
  • 2012
  • Ingår i: Journal of ultrasound in medicine. - : American Institute for Ultrasound in Medicine. - 0278-4297 .- 1550-9613. ; 31:3, s. 361-371
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives— The feasibility of visualizing atherosclerotic plaque using parametric subharmonic intravascular ultrasound (IVUS) was investigated in vivo.                    Methods— Atherosclerosis was induced in the aorta of 2 rabbits. Following injection of Definity (Lantheus Medical Imaging, North Billerica, MA), radiofrequency IVUS signals were acquired at 40 MHz with a Galaxy IVUS scanner (Boston Scientific/Scimed, Natick, MA).        Subharmonic imaging (SHI; receiving at 20 MHz) was performed offline by applying an 8-order equalization filter. Contrast-to-tissue ratios (CTRs) were computed for the vessel relative to the plaque area over 4 time points. Contrast-to-tissue ratios were also calculated for the plaque-tissue and vessel-tissue from 4 tissue regions of interest at 4 time points. Finally, parametric images showing the cumulative maximum intensity (CMI), time to peak, perfusion (PER), and time-integrated intensity (TII) were generated for the fundamental and subharmonic data sets, and CTR measurements were repeated.                    Results— Injection of the contrast agent resulted in improved delineation between plaque and the vessel lumen. Subharmonic imaging resulted in noticeable tissue suppression, although the intensity from the contrast agent was reduced. No improvement in the plaque to vessel lumen CTR was observed between the subharmonic and fundamental IVUS (2.1 ± 3.64 versus 2.2 ± 4.20; P = .5). However, the CTR for plaque-tissue was improved (11.8 ± 7.32 versus 9.9 ± 7.06; P < .0001) for SHI relative to fundamental imaging. Cumulative-maximum-intensity and TII maps of both fundamental and subharmonic data provided increased CTRs relative to nonparametric data sets (P < .002). Additionally, the CMI, PER, and TII of SHI IVUS showed significantly improved vessel-plaque CTRs relative to the fundamental (P < .04).                    Conclusions— Parametric SHI IVUS of atherosclerotic plaque is feasible and improves the visualization of the plaque.
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2.
  • Eriksson Crommert, Martin, 1974-, et al. (författare)
  • Can Sonography Be Used to Estimate Deep Abdominal Muscle Activation in Different Static Arm Positions While Standing?
  • 2017
  • Ingår i: Journal of ultrasound in medicine. - Laurel, USA : American Institute for Ultrasound in Medicine. - 0278-4297 .- 1550-9613. ; 36:1, s. 129-139
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: The aim of this study was to investigate whether sonography is a reliable tool for measuring deep abdominal muscle activation in different static arm positions while standing.Methods: Sonographic recordings were made of the transversus abdominis and obliquus internus abdominis in 4 different static arm positions that varied with regard to the postural demand and loading direction posed on the trunk. Ten nonconsecutive repetitions of each arm position were performed, and thickness measurements were made at 2 locations within each muscle. Reliability was analyzed by the generalizability theory; comparisons regarding thickness measurements were made by repeated-measures analyses of variance; and fascial sliding was analyzed by a 1-sample t test.Results: Averaged over all repetitions, arm positions, and the 2 measurement locations, the thickness measurements were highly reliable for both the obliquus internus abdominis and transversus abdominis. The transversus abdominis was thicker with shoulders flexed than with shoulders extended or arms above the head (P < .021) and with arms alongside the body compared with shoulders extended (P < .005). There was no thickness difference between arm positions for the obliquus internus abdominis (P = .059).Conclusions: The results indicate that sonographic recordings of the obliquus internus abdominis and transversus abdominis in different static arm positions while standing provide reliable measurements of muscle thickness. However, in light of previously reported electromyographic data, the results raise some concerns regarding the validity of using thickness measurements as proxies for muscle activation in positions that may induce passive muscle deformation.
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  • Grishenkov, Dmitry, 1983-, et al. (författare)
  • In search of the optimal ultrasound heart perfusion imaging platform
  • 2015
  • Ingår i: Journal of ultrasound in medicine. - : Wiley. - 0278-4297 .- 1550-9613. ; 34:9, s. 1599-1605
  • Tidskriftsartikel (refereegranskat)abstract
    • ObjectiveQuantification of the myocardial perfusion by contrast echocardiography (CEC) remains a challenge. Existing imaging phantoms used to evaluate the performance of ultrasound scanners do not comply with perfusion basics in the myocardium, where perfusion and motion are inherently coupled.MethodsTo contribute towards an improvement, we developed a CEC perfusion imaging platform based on isolated rat heart coupled to the ultrasound scanner. Perfusion was assessed using three different types of contrast agent: dextran-based Promiten®, phospholipid-shelled SonoVue®, and polymer-shelled MB-pH5-RT. The myocardial video-intensity was monitored over time from contrast administration to peak and two characteristic constants were calculated using exponential fit (A representing capillary volume and b representing inflow velocity).ResultsAcquired experimental evidence demonstrates that the application of all three types of contrast agent allow ultrasonic estimation of myocardial perfusion in the isolated rat heart. Video-intensity maps show that an increase in contrast concentration increases the late plateau values, A, mimicking increased capillary volume. Estimated values of the flow, proportional to Axb, increase when the pressure of the perfusate column increases from 80 to 110 cm of water. This finding is in agreement with the true values of the coronary flow increase measured by the flowmeter attached to the aortic cannula.ConclusionsThe described CEC perfusion imaging platform holds promise for standardized evaluation and optimization of ultrasound contrast perfusion imaging where real time inflow curves at low acoustic power semi-quantitatively reflect coronary flow.
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  • Hallgren, C., et al. (författare)
  • Validating a Simplified Lung Ultrasound Protocol for Detection and Quantification of Pulmonary Edema in Patients With Chronic Kidney Disease Receiving Maintenance Hemodialysis
  • 2023
  • Ingår i: Journal of Ultrasound in Medicine. - : Wiley. - 0278-4297 .- 1550-9613. ; 42:9, s. 2013-2021
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives Pulmonary edema is a common clinical problem and lung ultrasound (LUS) presents an efficient method for evaluating this pathology. This study aims to investigate if a clinically efficient LUS protocol can quantify the level of extravascular lung fluid in patients receiving hemodialysis, and to develop a simplified B-line scoring system based on this protocol.Methods A simple 8-area LUS approach was used for the assessment of the extravascular fluid status in patients before, during, and after receiving hemodialysis. The LUS assessments were compared to the amount of removed fluid over time. To determine the best B-line score system, different scorings for each zone were tested in a linear mixed model with pseudo R-square model fit against removed fluid. The B-line score was further validated through correlations with changes in oxygen saturation, grade of dyspnea, and body weight over time.Results A total of 53 patients were included and examined on 108 hemodialysis occasions. Median fluid removal was 2.3 L. The B-line score model with best fit was a score of 0 points in a zone with 0 or 1 B-lines, 1 point with 2 or 3 B-lines, 2 points with 3 or more B-lines, and 3 points with any interstitial confluence. Using this B-line score, we found a significant association with amount of removed fluid, oxygen saturation, grade of dyspnea, and change in body weight.Conclusion A straightforward protocol for LUS and B-line score system was shown valid for quantification of pulmonary edema and fluid removal in hemodialysis patients. The scoring system developed here can be useful also in other patient groups, but this requires further validation.
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6.
  • Hilde, K., et al. (författare)
  • Fetal Thoracic Circumference and Lung Volume and Their Relation to Fetal Size and Pulmonary Artery Blood Flow
  • 2022
  • Ingår i: Journal of Ultrasound in Medicine. - : Wiley. - 0278-4297 .- 1550-9613. ; 41:4, s. 985-993
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective Research on early origins of lung disease suggests the need for studying the relationships of thoracic and lung size with fetal size and pulmonary circulation. The primary aim of this study is therefore to explore the associations between fetal thoracic circumference, lung volume, and fetal size. We also aim to assess if lung volume and thoracic circumference are associated with fetal pulmonary artery blood flow velocity measures. Methods Cross-sectional assessment of singleton pregnancies from the general population (n = 447) at 30 gestational weeks (GW) was performed using ultrasound measurement of fetal thoracic circumference, lung volume, head and abdominal circumference, and femur length. We obtained Doppler blood flow velocity measures from the proximal branches of the fetal pulmonary artery. Associations between variables were studied using Pearson's correlation and multiple linear regression analyses. Results Both thoracic circumference and lung volume correlated with fetal size measures, ranging from r = 0.64 between thoracic circumference and abdominal circumference, to r = 0.28 between lung volume and femur length. Adjustment for gestational age, maternal nicotine use, pre-pregnancy body mass index, and fetal sex marginally influenced the associations with abdominal circumference. The correlations of thoracic circumference and lung volume with pulmonary artery blood flow velocity measures were weak (r <= 0.17). Conclusion We found moderate to low correlation between thoracic circumference, lung volume, and fetal size at 30 GW. The closest relationship was with the abdominal circumference. We found low correlations of thoracic circumference and lung volume with pulmonary artery blood flow velocity measures.
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  • Khosravi, Fariba, et al. (författare)
  • Scapular Upward Rotator Morphologic Characteristics in Individuals With and Without Forward Head Posture : A Case-Control Study
  • 2019
  • Ingår i: Journal of ultrasound in medicine. - : John Wiley & Sons. - 0278-4297 .- 1550-9613. ; 38:2, s. 337-345
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives There are several reports suggesting that forward head posture contributes to alterations in scapular kinematics and muscle activity, leading to the development of shoulder problems. Currently, it is unknown whether forward head posture alters the thickness of the scapular muscles. The aim of this study was to compare the thickness of the serratus anterior and upper and lower trapezius muscles at rest and during loaded isometric contractions in individuals with and without forward head posture. Methods Twenty individuals with forward head posture and 20 individuals with normal head posture participated in this case-control study. Three separate ultrasound images of the serratus anterior and upper and lower trapezius muscles were captured under 2 randomized conditions: at rest and during a loaded isometric contraction. Results The thickness of each muscle significantly increased from rest to the loaded isometric contraction (P?
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  • Larsson, Anna-Karin, et al. (författare)
  • Parents’ Worried State of Mind When Fetal Ultrasound Shows an Unexpected Finding
  • 2009
  • Ingår i: Journal of ultrasound in medicine. - 0278-4297 .- 1550-9613. ; 28:12, s. 1663-1670
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective. Most parents yearn for a second-trimester ultrasound examination and feel excitement about it, but some also worry about what the examination will show. According to prior research, using only generic instruments or specific questionnaires, anxiety decreases when the ultrasound findings are normal. The aim of this study was to compare parents’ worry (Parents’ Expectations, Experiences, and Reactions to Ultrasound [PEER-U] State of Mind Index) and sense of coherence before and after a routine second-trimester ultrasound examination when it showed normal or abnormal findings. Methods. A 1-year cohort study was performed at a Swedish university hospital. A total of 2049 parents who had their second-trimester ultrasound examinations there filled in a questionnaire consisting of 2 parts before and after the examinations. Results. Parents with normal ultrasound findings were less worried than parents with abnormal findings. The group with normal findings also showed less worry after the examination than before. A sex analysis showed similar patterns. Conclusions. Parents with abnormal ultrasound findings are more worried and anxious. The new instrument, the PEER-U State of Mind Index, not only measures parents’ worry but can also expose what influences their ultrasound examination experience.
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  • Lindström, Stefan B, 1974-, et al. (författare)
  • Computer-Aided Evaluation of Blood Vessel Geometry From Acoustic Images
  • 2018
  • Ingår i: Journal of ultrasound in medicine. - : Wiley-Blackwell Publishing Inc.. - 0278-4297 .- 1550-9613. ; 37:4, s. 1025-1031
  • Tidskriftsartikel (refereegranskat)abstract
    • A method for computer-aided assessment of blood vessel geometries based on shape-fitting algorithms from metric vision was evaluated. Acoustic images of cross sections of the radial artery and cephalic vein were acquired, and medical practitioners used a computer application to measure the wall thickness and nominal diameter of these blood vessels with a caliper method and the shape-fitting method. The methods performed equally well for wall thickness measurements. The shape-fitting method was preferable for measuring the diameter, since it reduced systematic errors by up to 63% in the case of the cephalic vein because of its eccentricity.
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  • Rohlén, Robin, et al. (författare)
  • Interframe Echo Intensity Variation of Subregions and Whole Plaque in Two-Dimensional Carotid Ultrasonography : Simulations and in Vivo Observations
  • 2023
  • Ingår i: Journal of ultrasound in medicine. - : John Wiley & Sons. - 0278-4297 .- 1550-9613. ; 42:5, s. 1033-1046
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: The risk of cardiovascular disease is associated with the echo intensity of carotid plaques in ultrasound images and their cardiac cycle-induced intensity variations. In this study, we aimed to 1) explore the underlying origin of echo intensity variations by using simulations and 2) evaluate the association between the two-dimensional (2D) spatial distribution of these echo intensity variations and plaque vulnerability.Methods: First, we analyzed how out-of-plane motion and compression of simulated scattering spheres of different sizes affect the ultrasound echo intensity. Next, we propose a method to analyze the features of the 2D spatial distribution of interframe plaque echo intensity in carotid ultrasound image sequences and explore their associations with plaque vulnerability in experimental data.Results: The simulations showed that the magnitude of echo intensity changes was similar for both the out-of-plane motion and compression, but for scattering objects smaller than 1 mm radius, the out-of-plane motion dominated. In experimental data, maps of the 2D spatial distribution of the echo intensity variations had a low correlation with standard B-mode echo intensity distribution, indicating complementary information on plaque tissue composition. In addition, we found the existence of ∼1 mm diameter subregions with pronounced echo intensity variations associated with plaque vulnerability.Conclusions: The results indicate that out-of-plane motion contributes to intra-plaque regions of high echo intensity variation. The 2D echo intensity variation maps may provide complementary information for assessing plaque composition and vulnerability. Further studies are needed to verify this method's role in identifying vulnerable plaques and predicting cardiovascular disease risk.
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14.
  • Röhl, Samuel, et al. (författare)
  • Noninvasive in vivo Assessment of the Re-endothelialization Process Using Ultrasound Biomicroscopy in the Rat Carotid Artery Balloon Injury Model.
  • 2019
  • Ingår i: Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine. - : Wiley. - 1550-9613. ; 38:7, s. 1723-1731
  • Tidskriftsartikel (refereegranskat)abstract
    • Ultrasound biomicroscopy (UBM), or ultra high-frequency ultrasound, is a technique used to assess the anatomy of small research animals. In this study, UBM was used to assess differences in intimal hyperplasia thickness as a surrogate measurement of the re-endothelialization process after carotid artery balloon injury in rats.Ultrasound biomicroscopic data from 3 different experiments and rat strains (Sprague Dawley, Wistar, and diabetic Goto-Kakizaki) were analyzed. All animals were subjected to carotid artery balloon injury and examined with UBM (30-70 MHz) 2 and 4 weeks after injury. Re-endothelialization on UBM was defined as the length from the carotid bifurcation to the most distal visible edge of the intimal hyperplasia. En face staining with Evans blue dye was performed at euthanasia 4 weeks after injury, followed by tissue harvesting for histochemical and immunohistochemical evaluations.A significant correlation (Spearman r=0.63; P<.0001) was identified when comparing all measurements of re-endothelialization obtained from UBM and en face staining. The findings revealed a similar pattern for all rat strains: Sprague Dawley (Spearman r=0.70; P<.0001), Wistar (Spearman r=0.36; P<.081), and Goto-Kakizaki (Spearman r=0.70; P<.05). A Bland-Altman test showed agreement between en face staining and UBM. Immunohistochemical staining confirmed the presence of the endothelium in the areas detected as re-endothelialized by the UBM assessment.Ultrasound biomicroscopy can be used for repeated in vivo assessment of re-endothelialization after carotid artery balloon injury in rats.
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  • Seiler, Claudia, et al. (författare)
  • Lung Ultrasound for Identification of Patients Requiring Invasive Mechanical Ventilation in COVID-19
  • 2021
  • Ingår i: Journal of ultrasound in medicine. - : John Wiley & Sons. - 0278-4297 .- 1550-9613. ; 40:11, s. 2339-2351
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: Indication for invasive mechanical ventilation in COVID-19 pneumonia has been a major challenge. This study aimed to evaluate if lung ultrasound (LUS) can assist identification of requirement of invasive mechanical ventilation in moderate to severe COVID-19 pneumonia.Materials and Methods: Between April 23 and November 12, 2020, hospitalized patients with moderate to severe COVID-19 (oxygen demand >= 4 L/min) were included consecutively. Lung ultrasound was performed daily until invasive mechanical ventilation (IMV-group) or spontaneous recovery (non-IMV-group). Clinical parameters and lung ultrasound findings were compared between groups, at intubation (IMV-group) and highest oxygen demand (non-IMV-group). A reference group with oxygen demand <4 L/min was examined at hospital admission.Results: Altogether 72 patients were included: 50 study patients (IMV-group, n = 23; non-IMV-group, n = 27) and 22 reference patients. LUS-score correlated to oxygen demand (SpO(2)/FiO(2)-ratio) (r = 0.728; p < 0.0001) and was higher in the IMV-group compared to the non-IMV-group (20.0 versus 18.0; p = 0.026). Based on receiver operating characteristic analysis, a LUS-score of 19.5 was identified as cut-off for requirement of invasive mechanical ventilation (area under the curve 0.68; sensitivity 56%, specificity 74%). In 6 patients, LUS identified critical coexisting conditions. Respiratory rate and oxygenation index ((SpO(2)/FiO(2))/respiratory rate) >= 4.88 identified no requirement of invasive mechanical ventilation with a positive predictive value of 87% and negative predictive value of 100%.Conclusions: LUS-score had only a moderate diagnostic value for requirement of invasive mechanical ventilation in moderate to severe COVID-19. However, LUS proved valuable as complement to respiratory parameters in guidance of disease severity and identifying critical coexisting conditions.
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  • Stenman, Carina, et al. (författare)
  • Do Radiologists Agree on Findings in Radiographer-Acquired Sonographic Examinations?
  • 2013
  • Ingår i: Journal of ultrasound in medicine. - : American Institute of Ultrasound in Medicine. - 0278-4297 .- 1550-9613. ; 32:3, s. 513-518
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVES:Sonographic examinations are usually regarded as observer dependent, but a recently introduced method using documentation with cine loops acquired in a standardized way attempts to address this problem. The aim of this study was to evaluate the intraobserver and interobserver agreement of sonographic liver examinations using strictly standardized examination protocols with cine loop documentation.METHODS:Ninety-eight outpatients were examined by a radiographer using the standardized method. Three radiologists, each with 10 to 20 years of experience in sonography, reviewed the cine loops retrospectively. After 4 weeks, the review was repeated; the 3 radiologists were blinded to the initial reading. The κ coefficient was used to analyze intraobserver and interobserver agreement, and agreement in percent was also calculated.RESULTS:The intraobserver agreement was highest for concrements in the gallbladder (κ= 0.91-0.96) and lowest when assessing the need for further examination (κ = 0.38-0.64). For increased liver echogenicity, κ varied between 0.73 and 0.92 and for skip areas between 0.73 and 0.90. The interobserver agreement was also highest for concrements in the gallbladder (κ = 0.84-1.00) and lowest for the need for further examination (κ = -0.12-0.46). For most other findings, substantial intraobserver agreement was found.CONCLUSIONS:For sonographic examinations performed according to a standardized examination protocol by a radiographer and viewed by an experienced radiologist, good interobserver agreement was found, except for judgments of the need for further examinations.
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  • Thunswärd, Per, et al. (författare)
  • Filling of Fine and Core Biopsy Needles With the Contrast Agent Sulfur Hexafluoride : Ex Vivo and in vitro Evaluation of Ultrasound Needle Visibility.
  • 2020
  • Ingår i: Journal of ultrasound in medicine. - : Wiley. - 0278-4297 .- 1550-9613. ; 39:11, s. 2133-2142
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVES: To investigate whether the ex vivo and in vitro ultrasound visibility of fine needles (FNs) and core biopsy needles (CNBs) can be improved by filling them with an ultrasound contrast agent.METHODS: After needle filling with the contrast agent sulfur hexafluoride, punctures with FNs and CBNs were recorded in the B-mode and contrast-specific imaging mode (10 observations in each of the 4 groups). Recordings were made in both butchered bovine liver (experiment I) and a water bath (experiment II). Air and normal saline were used as controls (total n = 120 for each experiment). In experiment I, 4 ultrasound specialists subjectively assessed the relative needle visibility in the recordings by using an arbitrary scale (integers 0-10). In experiment II, the contrast-to-noise ratio was calculated for both the entire needle course and the needle tip area.RESULTS: In experiment I, subjective visibility was increased compared with both controls only for CBNs in the contrast-specific imaging mode (P < .01). In experiment II, the contrast-to-noise ratio for both the entire needle course and the needle tip area increased compared with both controls for both FNs and CBNs in the contrast-specific imaging mode (P < .05).CONCLUSIONS: Ultrasound contrast agent needle filling is a promising new method to increase the visibility of CBNs in the contrast-specific imaging mode. This finding needs to be confirmed in vivo before its clinical value can be assessed.
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  • Wang, Page I., et al. (författare)
  • Sonographically Guided Lumbar Puncture in Pediatric Patients
  • 2013
  • Ingår i: Journal of Ultrasound in Medicine. - : Wiley. - 1550-9613 .- 0278-4297. ; 32:12, s. 2191-2197
  • Tidskriftsartikel (refereegranskat)abstract
    • Our aim with this study was to develop a user-friendly method for pediatric sonographically guided lumbar punctures so that we can visualize intrathecal anatomy, confirm intrathecal injection at the time of injection, and, most importantly, avoid ionizing radiation to a child's already radiosensitive pelvis. Sonographically guided lumbar puncture was prospectively performed in children aged 7 weeks to 16 years. All attempts (n = 9) were successful. We were able to identify relevant anatomy (including the conus in children 10 years and younger), confirm intrathecal injection, visualize intrathecal hematoma, and avoid radiation. Sonography is a promising modality for image-guided lumbar punctures without radiation in children.
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  • Aad, G., et al. (författare)
  • 2012
  • Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368 .- 1550-7998. ; 86:7
  • Tidskriftsartikel (refereegranskat)
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  • Braide, Magnus, 1955, et al. (författare)
  • Microvascular behavior and effects of sonazoid microbubbles in the cremaster muscle of rats after local administration.
  • 2006
  • Ingår i: Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine. - 0278-4297. ; 25:7, s. 883-90
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: The purpose of this study was to observe Sonazoid perfluorobutane microbubbles (GE Healthcare, Amersham, Buckinghamshire, England) in and their effects on the cremaster capillary microcirculation of rats. METHODS: Sonazoid (0.3 x 10(9) microbubbles in 0.5 mL) was observed by intravital microscopy in the cremaster muscle after retrograde administration into the femoral artery of 6 animals. Microbubble and microvessel diameters and blood flow velocities and the overall mean and SD of the 1-minute volume flow through the microscopic field were calculated from the 2 to 4 capillaries observed in the field of each animal. Fluorescein isothiocyanate-dextran leakage was used to assess extravasation after microbubble passage. RESULTS: seconds, respectively, before they were released and capillary flow normalized. No microbubble size changes, damming, or coalescence of bubbles and no changes in microvessel diameter or microvascular blood flow velocities, volume flow, or perfusion heterogeneity occurred during or after the passage of the Sonazoid suspension or the vehicle. No fluorescein isothiocyanate-dextran leakage was observed. CONCLUSIONS: The passage of Sonazoid bubbles at concentrations higher than those expected after intravenous administration of the Sonazoid did not durably impair microvascular perfusion, structural integrity, or macromolecular retention in the rat cremaster muscle. The duration of discrete capillary obstructions was short and in all cases comparable with that of naturally occurring leukocyte plugging.
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  • Crang Svalenius, Elizabeth, et al. (författare)
  • Intrauterine growth of the fetus at term. A prospective and longitudinal study with real-time ultrasound
  • 1990
  • Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 9:1, s. 35-38
  • Tidskriftsartikel (refereegranskat)abstract
    • Intrauterine fetal growth was followed in a prospective study of 654 consecutive singleton pregnancies. Ultrasound fetometry was performed in gestational weeks 17, 32, and 39, and then weekly until delivery took place. A total of 408 fetuses were examined in the 39th week and 55 investigations were performed in the postterm period. This enabled us to follow the intrauterine growth of the normal fetus both at term and postterm. We found that the intrauterine rate of growth continued constantly, even postterm, for the biparietal diameter, abdominal diameter, and femur length.
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  • Crang Svalenius, Elizabeth, et al. (författare)
  • Normal ultrasonic fetal growth ratios evaluated in cases of fetal disproportion
  • 1991
  • Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 10:2, s. 89-92
  • Tidskriftsartikel (refereegranskat)abstract
    • During a 2-year period, 5476 normal routine obstetrical ultrasound investigations were performed in the 2nd trimester (16th to 20th week). Data on biparietal diameter (BPD), abdominal diameter (AD) and femur length (FL) have been obtained from this material. Ratios between BPD/AD and BPD/FL have been calculated, and from these ratios, graphs were constructed. Only nine normal fetuses (0.2%) were found to be outside mean +/- 3 SD, and none of the normal cases were +/- 4 SD, so this is perhaps a better guideline for those warranting further investigation. To evaluate if these ratios could better reflect disproportional fetal growth, three cases of triploidy and four cases of dwarfism were tested against these ratios. Triploidy was obvious on the BPD/AD graph and dwarfism on the BPD/FL graph. The ratios were not found to be conclusive in the intrauterine diagnosis of trisomy 21 or of trisomy 18, as only 4 of 17 cases were obvious on the graphs.
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  • Jokubkiene, Ligita, et al. (författare)
  • Number of antral follicles, ovarian volume, and vascular indices in asymptomatic women 20 to 39 years old as assessed by 3-dimensional sonography: a prospective cross-sectional study.
  • 2012
  • Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 31:10, s. 1635-1649
  • Tidskriftsartikel (refereegranskat)abstract
    • Objectives: Our aim was to elicit data representative of normal findings on 3-dimensional (3D) transvaginal gray-scale and power Doppler sonography of ovaries in women of fertile age. Methods: A total of 303 gynecologically asymptomatic white women 20 to 39 years old with spontaneous regular menstrual cycles were examined with transvaginal 3D gray-scale and power Doppler sonography on cycle days 4 to 8. We used a 6- to 12-MHz transducer. The ovarian volume, number and volume of antral follicles of 2 mm or larger, vascularization index, flow index, and vascularization-flow index were calculated using dedicated software. Results are presented separately for women with follicles of 2.0 to 10.0 mm and for those with at least 1 follicle larger than 10.0 mm for 3 age groups: 20 to 29, 30 to 34, and 35 to 39 years. Results: There were 214 women (71%) with follicles of 2.0 to 10.0 mm and 89 (29%) with follicles larger than 10.0 mm. In women with follicles of 2.0 to 10.0 mm, the right ovary was on average 0.8 cm(3) larger and contained on average 1.2 more follicles than the left one. The ovarian volume, number of follicles, and total follicular volume decreased significantly with age in both ovaries (P = .000-.029): for the right ovary ovarian volume, the median (range) decreased from 8.4 (3.7-17.3) cm(3) at 20 to 29 years to 6.5 (2.4-12.7) cm(3) at 35 to 39 years, the number of follicles from 14 (1-32) at 20 to 29 years to 8 (1-21) at 35 to 39 years, and the total follicular volume from 1.08 (0.01-3.10) cm(3) at 20 to 29 years to 0.84 (0.03-2.00) cm(3) at 35 to 39 years. The size of the largest follicle and the vascular indices manifested no clear changes with age in any ovary. In women with follicles larger than 10 mm, the number of follicles decreased with age in both ovaries. Conclusions: We have elicited data representative of normal findings on 3D trans-vaginal sonography of ovaries in gynecologically asymptomatic white women of fertile age. Our gray-scale sonographic results may be used as reference values for general gynecology in populations similar to ours. Vascular indices must be interpreted with caution because of difficulties with standardization.
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  • Sladkevicius, Povilas, et al. (författare)
  • Transvaginal Doppler examination for the differential diagnosis of solid pelvic tumors
  • 1995
  • Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 14:5, s. 377-5380
  • Tidskriftsartikel (refereegranskat)abstract
    • To evaluate the ability of transvaginal Doppler examination to discriminate between different types of solid pelvic tumors, 55 women scheduled for laparotomy because of a solid pelvic mass underwent transvaginal sonographic examination, including color and spectral Doppler techniques. Arteries in the wall and core of each mass were examined. The histological diagnoses were as follows: uterine myoma (n = 28), malignant ovarian tumor (n = 19), and benign ovarian tumor (n = 8). Pulsatility index values tended to be highest in the malignant ovarian tumors, albeit with considerable overlap with respect to the other tumor types. The respective median pulsatility index values for arteries in the wall and core of the malignant ovarian tumors were 0.93 and 0.87, versus 0.65 and 0.51 in the benign ovarian tumors and 0.80 and 0.67 in the myomas. Time-averaged maximum velocity did not differ significantly among the three types of tumor. We conclude that Doppler measurement of blood flow velocity in tumor arteries does not add substantial information to the differential diagnosis between myomas and benign or malignant solid ovarian tumors.
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32.
  • Örnö, Ann-Kristin, et al. (författare)
  • Sonographic visualization of the rectoanal inhibitory reflex in children suspected of having hirschsprung disease: a pilot study.
  • 2008
  • Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 27:8, s. 1165-1169
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: To date, for detection of the absence of peristalsis in children with chronic constipation and a suspicion of Hirschsprung disease (HD), children have been investigated with a contrast enema. If the radiographic investigation is inconclusive, anometry and a rectal biopsy are performed. A new noninvasive real-time sonographic method for examination of the rectoanal inhibitory reflex (RAIR) was compared with anometry. METHODS: The rectum and anal canal of children were visualized transperineally on sonography. The RAIR was elicited by injecting water into the rectum, and the events in the bowel were recorded on video for offline analysis. RESULTS: Injection of water initiated a peristaltic wave that moved the rectal contents into the proximal part of the anal canal in healthy children. Among 28 children with suspected HD, 3 showed aganglionosis in their biopsy samples. These 3 children lacked the RAIR according to both sonography and anometry. Both methods had a negative predictive value of 100%. In 17 children, the RAIR was present according to both sonography and anometry, and all of these children had normal histologic findings. In 8 children, sonography did not show the reflex despite normal histologic findings; in 2 of these, the quality of the investigation made the evaluation uncertain. CONCLUSIONS: This pilot study indicates that in children with chronic constipation, a transperineal sonographic examination of the RAIR is comparable to anometry and can facilitate the diagnose of HD.
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