Ultrasound Measurements (ultrasound + measurement)

Distribution by Scientific Domains


Selected Abstracts


Choosing the location for non-image guided abdominal paracentesis

LIVER INTERNATIONAL, Issue 5 2005
Hideki Sakai
Abstract: Objectives: The optimal location for paracentesis has not been studied scientifically. The evolving obesity epidemic has changed the physique of many patients with cirrhosis and ascites such that needles inserted into the abdominal wall may not reach fluid. We aimed to determine the location for paracentesis that would have the thinnest abdominal wall and the deepest amount of fluid. Methods: Ultrasound measurements of abdominal wall thickness and depth of ascites were recorded in two locations, the infraumbilical midline (ML) and the left lower quadrant (LLQ), in 52 patients with cirrhosis and ascites admitted to a single inpatient liver unit. Results: The abdominal wall was significantly thinner (1.8 vs. 2.4 cm; P<0.001) and the depth of ascites greater (2.86 vs. 2.29 cm; P=0.017) in the LLQ as compared with the infraumbilical ML position. In the left lateral oblique position, the difference in the depth of ascites was more pronounced when comparing the LLQ with the infraumbilical ML (4.57 vs. 2.78 cm; P<0.0001). Conclusions: The LLQ is preferable to the ML infraumbilical location for performing paracentesis. [source]


Oculometry findings in high myopia at adult age: considerations based on oculometric follow-up data over 28 years in a cohort-based Danish high-myopia series

ACTA OPHTHALMOLOGICA, Issue 4 2010
Hans C. Fledelius
Abstract. Purpose:, To present and discuss oculometry data in a series of adults with high myopia followed between the ages of 26 and 54 years. Emphasis is on axial length (AL) findings and corneal curvature radius (Crad). Methods:, Thirty-four out of the 39 individuals recruited as teenagers from a Copenhagen 1948 birth cohort with myopia of at least 6 D have had current follow-up exams, to include AL measurements (by ultrasound, 1974,2002; the latter year also with the Zeiss IOLMaster) and keratometry. The cross-sectional and longitudinal analyses are based primarily on the eyes with high myopia; however, the fellow eye is also assessed in unilateral cases. Results:, At age 54 years, the maximum myopia in the series was ,26 D; the highest AL value was 35.4 mm. The myopia had increased in most, with an increase from the 26-year oculometry baseline averaging 1.0 D [standard deviation (SD) 1.84]. Ultrasound measurements over the 28 years gave a significant correlation between axial eye elongation and myopia progression of adult age (r = 0.65). The regression line was y = 0.43 + 0.36x, with myopia increase on the x-axis. Throughout sessions, the association between AL and refraction was given by correlation coefficients numerically above 0.8, whereas AL and Crad had r -values of 0.3,0.5. However, a mean Crad in the sample of 7.66 (SD 0.28) mm meant that the more general expectancy of rather flat corneas in high myopia was not fulfilled. Our data further suggested a reduction in lens power over the study period. Conclusion:, In relation to refraction, AL and Crad remain the two main oculometry parameters. Apparently the correlation patterns regarding the cornea that are broadly valid for axial ametropia in the population cannot be extended to the marginal high myopia tail of the distribution. A significant proportion of eyes with high myopia thus had steeper corneas than expected, as a so-called index contribution (albeit a small one) to the marginal refractive error. [source]


Ultrasound measurements of the lateral ventricles in neonates: why, how and when?

ACTA PAEDIATRICA, Issue 9 2010
A systematic review
Abstract Germinal matrix-intraventricular haemorrhage and subsequent post-haemorrhagic ventricular dilatation (PHVD) are frequently encountered complications in preterm neonates. As progressive dilatation of the lateral ventricles may be associated with elevated intracranial pressure, ultrasound measurements of ventricular size play a major role in the evaluation of neonates at risk of ventricular dilatation as well as in assessing the effect of intervention for PHVD. A systematic search was carried out in Medline and Embase to identify neonatal and foetal ultrasound studies on lateral ventricular size. This review presents an overview of the available data concerning neonatal reference values for lateral ventricular size, the influence of gender, ventricular asymmetry and the effect of the mode of delivery on the phenomenon of ventricular reopening following birth. Conclusion:, Serial cranial ultrasound measurements of the lateral ventricles play a key role in the early recognition and therapeutic evaluation of post-haemorrhagic ventricular dilation and can be of prognostic value in neonates with ventricular dilatation. [source]


Assessment of renal function with color Doppler ultrasound in autosomal dominant polycystic kidney disease

INTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2001
Akira Kondo
Abstract Background: Measurement of renal blood flow by color Doppler ultrasound is useful for assessment of renal function in a variety of renal disorders. In autosomal dominant polycystic kidney disease (ADPKD), however, it might be difficult to visualize interlobar arteries because of deformity of renal structure. To evaluate the usefulness of color Doppler in ADPKD, parameters determined by blood flow examination were compared with the results of ordinal renal function tests. Methods: Twenty-one patients with ADPKD were examined by color Doppler ultrasound measurement. In each patient, 10 interlobar arteries in both kidneys were investigated. Minimum blood flow velocity (Vmin), maximum blood flow velocity (Vmax), mean blood flow velocity (Vmean), acceleration, resistive index and pulsatility index were measured in relation to the results of creatinine clearance, serum creatinine, blood urea nitrogen and 15 and 120 min values of the phenolsulfonphthalein test. Results: In all patients, interlobar arteries were able to be visualized and blood-flow profile was measured. Although variations of Vmin, Vmax, Vmean and acceleration were relatively large, the resistive index and pulsatility index varied little in each kidney. Mean values of Vmin (P < 0.005), Vmean (P < 0.05), resistive index (P < 0.005) and pulsatility index (P < 0.005) were well correlated to creatinine clearance with statistical significance. Conclusions: In ADPKD, color Doppler ultrasound measurement is a useful method for assessment of renal function and could be used for monitoring the dynamic state of renal blood flow as a non-invasive technique. [source]


Ultrasound control for presumed difficult epidural puncture

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2001
T. Grau
Background: The efficacy of epidural anaesthesia depends on the accurate identification of the epidural space (ES). Abnormal anatomical conditions may make the procedure difficult or impossible. The aim of this study was to investigate whether pre-puncture ultrasound examination of the spinal anatomy might be beneficial in expected cases of difficult epidural anaesthesia. Methods: We used digital ultrasound equipment with a 5-MHz transducer to assess the anatomy of the ES and the posterior parts of the spinal column. We examined 72 parturients with abnormal anatomical conditions who were scheduled for epidural anaesthesia. The women were randomised into two equal groups. In all patients, the standard loss of resistance technique was used. In the ultrasound group, an ultrasound examination of the appropriate spinal region was conducted prior to epidural puncture. ES depth seen on the ultrasound images was compared to the ES depth measured by the needle. We compared the number of puncture attempts with the standard method (control group) to the number of attempts under ultrasound guidance. Results: Ultrasonography significantly improved operating conditions for epidural anaesthesia. The maximum VAS scores and patient acceptance were significantly better. Conclusions: With ultrasound measurement of the ES depth, the quality of epidural anaesthesia was enhanced. [source]


Contingent screening for Down syndrome,results from the FaSTER trial

PRENATAL DIAGNOSIS, Issue 2 2008
Howard S. Cuckle
Abstract Objective Comparison of contingent, step-wise and integrated screening policies. Methods Mid-trimester Down syndrome risks were retrospectively calculated from FaSTER trial data. For contingent screening, initial risk was calculated from ultrasound measurement of nuchal translucency (NT), maternal serum pregnancy-associated plasma protein (PAPP)-A and free ,-human chorionic gonadotrophin (hCG) at 11,13 weeks, and classified positive (>1 in 30), borderline (1 in 30,1500) or negative. Borderline risks were recalculated using ,-fetoprotein, hCG, unconjugated estriol (uE3) and inhibin at 15,18 weeks, and reclassified as positive (>1 in 270) or negative. For step-wise screening, initial negative risks were also recalculated. For integrated screening, a single risk was calculated from NT, PAPP-A and the second trimester markers. Results There were 86 Down syndrome and 32 269 unaffected pregancies. The detection rate for contingent screening was 91% and false-positive rate was 4.5%; initial detection rate was 60%, initial false-positive rate was 1.2% and borderline risk was 23%. Step-wise screening had 92% detection rate and 5.1% false-positive rate; integrated screening had 88% and 4.9% respectively. Conclusion As predicted by modelling, the contingent screening detection rate for a fixed false-positive rate is comparable with step-wise and integrated screening, but substantially reduces the number needing to return for second trimester testing. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Increased thickness of the arterial intima-media detected by ultrasonography in patients with rheumatoid arthritis

ARTHRITIS & RHEUMATISM, Issue 6 2002
Yasuro Kumeda
Objective To determine whether arterial wall thickening is advanced in rheumatoid arthritis (RA) patients compared with healthy controls by measuring the intima-media thickness (IMT) of the common carotid and femoral arteries, and to evaluate the factors associated with arterial IMT in patients with RA. Methods We studied 138 RA patients and 94 healthy controls (matched for age, sex, and other major risk factors for atherosclerosis). IMT was measured on digitized still images of the common carotid and femoral arteries obtained by high-resolution ultrasonography (10-MHz in-line Sectascanner). Laboratory variables relevant to RA activity were measured by routine methods. The degree of RA progression was assessed by scoring (Larsen method) metacarpophalangeal (MCP) joints on hand radiographs. Activities of daily living were determined by a modified Health Assessment Questionnaire (M-HAQ) score, and physical activity levels were assessed by ultrasound measurement of the calcaneus (expressed as the osteo-sono assessment index [OSI] Z score). Results Common carotid and femoral artery IMTs were significantly higher (P < 0.05) in RA patients (mean ± SD 0.641 ± 0.127 and 0.632 ± 0.125 mm, respectively) compared with controls (0.576 ± 0.115 and 0.593 ± 0.141 mm, respectively). Multiple regression analysis revealed a significant association between RA and the common carotid artery IMT. Moreover, the common carotid artery IMT in RA patients was positively associated with disease duration, the MCP joint Larsen score, and the M-HAQ score, and was negatively associated with the calcaneus OSI Z score. No significant association was found between corticosteroid treatment and common carotid artery IMT. Conclusion RA patients exhibited greater thickness of the common carotid and femoral arteries than healthy controls. The duration and severity of RA and decreased activities of daily living, but not corticosteroid treatment, were independently associated with the increased arterial wall thickness. [source]


Primary predictors of preterm labour

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2005
François Goffinet
Spontaneous preterm birth accounts for 60% of all preterm births in developed countries. With the increase in multiple pregnancies, induced preterm birth and the progress in neonatal care for extremely preterm neonates, spontaneous preterm birth for singleton pregnancies in developed countries has probably decreased over the past 30 years. This decrease is likely to be related to better prenatal care for all pregnant women because the recognition of primary risk factors in early or late pregnancy remains a basic part of prenatal care. The failure to distinguish between induced and spontaneous preterm labour in most population-based studies makes it difficult to interpret results with respect to the primary predictors of preterm labour. Many such primary predictors of preterm labour have been used over the past 20,30 years. These include individual factors, socio-economic factors, working conditions and obstetric and gynaecological history. Risk scores have been proposed in order to produce these data. Unfortunately, the predictive value of these scores, especially their specificity, is poor, mainly because all of these factors are indirect. We still cannot identify the mechanisms that lead to preterm labour and birth. New markers more directly related to preterm labour have recently been proposed, some of which relate to direct causes of preterm labour such as cervical ultrasound measurement, fetal fibronectin (FFN), salivary estriol, serum CRH and bacterial vaginosis. Several of these have predictive values, which are potentially useful for clinical practice. Nonetheless, pregnant women in developed countries are already closely monitored throughout pregnancy. Before proposing new screening tests to be applied systematically to all pregnant women, their advantages and drawbacks must be fully evaluated. [source]


Fetal size in mid- and late pregnancy is related to infant alertness: The generation R study

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2009
Jens Henrichs
Abstract The vulnerability for behavioral problems is partly shaped in fetal life. Numerous studies have related indicators of intrauterine growth, for example, birth weight and body size, to behavioral development. We investigated whether fetal size in mid- and late pregnancy is related to infant irritability and alertness. In a population-based birth cohort of 4,255 singleton full-term infants ultrasound measurements of fetal head and abdominal circumference in mid- and late pregnancy were performed. Infant irritability and alertness scores were obtained by the Mother and Baby Scales at 3 months and z -standardized. Multiple linear regression analyses revealed curvilinear associations (inverted J-shape) of measures of fetal size in both mid- and late pregnancy with infant alertness. Fetal size characteristics were not associated with infant irritability. These results suggest that alterations of intrauterine growth affecting infant alertness are already detectable from mid-pregnancy onwards. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 51: 119,130, 2009 [source]


Assessment of the Tilting Properties of the Human Mitral Valve during Three Main Phases of the Heart Cycle: An Echocardiographic Study

ECHOCARDIOGRAPHY, Issue 4 2006
Daniel Vanhercke B.N., N.F.E.S.C., R.D.C.S.
Rationale and Objectives: In experimental models of the left heart, the mitral valve (MV) is commonly implanted perpendicular to a central axis of the apex/MV. To adapt this to a more correct anatomical model, as well as for further studies of the left ventricle, we created a database of implantation angles of the MV and annulus during three main phases of the heart cycle, based on standard cardiac ultrasound measurements. Materials and Methods: Twenty-eight patients were studied with the standard cardiac ultrasound equipment. From the apical echo window, an anteroposterior (AP) plane and a perpendicular commisure-commisure (CC) plane were generated during three critical moments in the heart cycle: systole (S); diastole early filling (E); and diastole late filling (A). In both planes, the angles between the annular plane and each mitral leaflet, as well as the angle between a theoretical longitudinal axis through the apex and center of the MV orifice and the mitral annulus plane, were measured with a custom-made application of Matlab R14. Results: We observed an inclination of the angle mitral annulus/central left ventricle axis, with its lowest point in the direction of the aortic valve (AP plane) of 85°± 7° in systole (S), 88°± 8° in early diastole (E), and 88°± 7° in late diastole (A). In the CC plane, we observed an almost horizontal implantation of 91°± 5° in systole (S), 91°± 8° in early diastole (E), and 91°± 7° in late diastole (A). [source]


Real-time Fourier velocity encoding: An in vivo evaluation

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2005
Christopher K. Macgowan PhD
Abstract Purpose To compare in vivo real-time Fourier velocity encoding (FVE), spectral-Doppler ultrasound, and phase-contrast (PC) magnetic-resonance (MR) imaging. Materials and Methods In vivo velocity spectra were measured in the suprarenal and infrarenal aorta and the hepatic segment of the inferior vena cava of eight normal volunteers using FVE, and compared to similar measurements using Doppler ultrasound and gated PC MR imaging. In vivo waveforms were compared qualitatively according to flow pattern appearance (number, shape, and position of velocity peaks) and quantitatively according to peak velocity. Results Good agreement was obtained between peak velocities measured in vitro using FVE and PC MR imaging (R2 = 0.99, P = 2.10,6, slope = 0.97 ± 0.05). Qualitatively, the FVE and ultrasound measurements agreed closely in the majority of in vivo cases (excellent or good in 21/24 cases) while the PC MR method resolved fewer velocity peaks due to the inherent temporal averaging of cardiac-gated studies (excellent or good agreement with FVE in 13/24 cases). Quantitatively, the FVE measurement of peak velocity correlated strongly with both ultrasound (R2 = 0.71, P = 2.10,7, slope = 0.81 ± 0.08) and PC MR (R2 = 0.85, P = 2.10,10, slope = 1.04 ± 0.08). Conclusion Real-time MR assessment of blood-flow velocity correlated well with spectral Doppler ultrasound. Such new methods may allow hemodynamic information to be acquired in vessels inaccessible to ultrasound or in patients for whom respiratory compensation is not possible. J. Magn. Reson. Imaging 2005;21:297,304. © 2005 Wiley-Liss, Inc. [source]


High-resolution blood flow velocity measurements in the human finger

MAGNETIC RESONANCE IN MEDICINE, Issue 4 2001
M. Klarhöfer
Abstract MR phase contrast blood flow velocity measurements in the human index finger were performed with triggered, nontriggered, and cine acquisition schemes. A strong (Gmax = 200 mT/m), small bore (inner diameter 12 cm) gradient system inserted in a whole body 3 Tesla MR scanner allowed high-resolution imaging at short echo times, which decreases partial volume effects and flow artifacts. Arterial blood flow velocities ranging from 4.9,19 cm/sec were measured, while venous blood flow was significantly slower at 1.5,7.1 cm/sec. Taking into account the corresponding vessel diameters ranging from 800 ,m to 1.8 mm, blood flow rates of 3.0,26 ml/min in arteries and 1.2,4.8 ml/min in veins are obtained. The results were compared to ultrasound measurements, resulting in comparable blood flow velocities in the same subjects. Magn Reson Med 45:716,719, 2001. © 2001 Wiley-Liss, Inc. [source]


Anatomical information is needed in ultrasound imaging of muscle to avoid potentially substantial errors in measurement of muscle geometry

MUSCLE AND NERVE, Issue 5 2009
Menno R. Bénard MSc
Abstract This study validates two-dimensional (2D) ultrasound measurements of muscle geometry of the human medial gastrocnemius (GM) and investigates effects of probe orientation on errors in these measurements. Ultrasound scans of GM muscle belly were made both on human cadavers (n = 4) and on subjects in vivo (n = 5). For half of the cadavers, ultrasound scans obtained according to commonly applied criteria of probe orientation deviated 15° from the true fascicle plane. This resulted in errors of fascicle length and fascicle angle up to 14% and 23%, respectively. Fascicle-like structures were detectable over a wide range of probe tilt and rotation angles, but they did not always represent true fascicles. Errors of measurement were either linear or quadratic functions of tilt angle. Similar results were found in vivo. Therefore, we conclude that similar errors are likely to occur for in vivo measurements. For all cadavers, at the distal end of GM, the true fascicle plane was shown to be perpendicular to the distal aponeurosis. Using transverse images of GM to detect the curvature of the deep aponeurosis at the distal end of the muscle belly is a simple strategy to help identify the fascicle plane. For subsequent longitudinal imaging, probe alignment within this plane will help minimize measurement errors of fascicle length, fascicle angle, and muscle thickness. Muscle Nerve, 2009 [source]


Body composition and its components in preterm and term newborns: A cross-sectional, multimodal investigation

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2010
Irfan Ahmad
A prospective, cross-sectional, observational study in preterm and term infants was performed to compare multimodal measurements of body composition, namely, limb ultrasound, bone quantitative ultrasound, and dual X-ray absorptiometry (DXA). One hundred and two preterm and term infants appropriate for gestational age were enrolled from the newborn nursery and neonatal intensive care unit. Infants were included when they were medically stable, in an open crib, on full enteral feeds and within 1 week of anticipated discharge. Correlations among the various measurements of body composition were performed using standard techniques. A comparison between preterm infant (born at 28,32 weeks) reaching term to term-born infants was performed. Limb ultrasound estimates of cross-sectional areas of lean and fat tissue in a region of tissue (i.e., the leg) were remarkably correlated with regional and whole-body estimates of fat-free mass and fat obtained from DXA suggesting the potential usefulness of muscle ultrasound as an investigative tool for studying aspects of body composition in this fragile population. There was a weak but significant correlation between quantitative ultrasound measurements of bone strength and DXA-derived bone mineral density (BMD). Preterm infants reaching term had significantly lower body weight, length, head circumference, muscle and fat cross-sectional area, bone speed of sound, whole-body and regional lean body mass, fat mass, and BMD compared to term-born infants. Current postnatal care and nutritional support in preterm infants is still unable to match the in-utero environment for optimal growth and bone development. The use of relatively simple bedside, noninvasive body composition measurements may assist in understanding how changes in different components of body composition early in life affect later growth and development. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source]


Ultrasound measurements of the lateral ventricles in neonates: why, how and when?

ACTA PAEDIATRICA, Issue 9 2010
A systematic review
Abstract Germinal matrix-intraventricular haemorrhage and subsequent post-haemorrhagic ventricular dilatation (PHVD) are frequently encountered complications in preterm neonates. As progressive dilatation of the lateral ventricles may be associated with elevated intracranial pressure, ultrasound measurements of ventricular size play a major role in the evaluation of neonates at risk of ventricular dilatation as well as in assessing the effect of intervention for PHVD. A systematic search was carried out in Medline and Embase to identify neonatal and foetal ultrasound studies on lateral ventricular size. This review presents an overview of the available data concerning neonatal reference values for lateral ventricular size, the influence of gender, ventricular asymmetry and the effect of the mode of delivery on the phenomenon of ventricular reopening following birth. Conclusion:, Serial cranial ultrasound measurements of the lateral ventricles play a key role in the early recognition and therapeutic evaluation of post-haemorrhagic ventricular dilation and can be of prognostic value in neonates with ventricular dilatation. [source]