Normal splenic volumes estimated using three-dimensional ultrasonography. (17/5805)

The purposes of this study were to determine splenic volumes using three-dimensional ultrasonography and to compare these measurements with two-dimensional splenic indices. Fifty-two healthy volunteers were studied. Two-dimensional volume measurements were based on length, width, and thickness, and the splenic index was calculated using the standard prolated ellipsoid formula (length x width x thickness x 0.523). Three-dimensional volume planar measurements were obtained with a slice by slice technique by manually drawing a region of interest around the spleen from one end of the sweep to the opposite end. These measurements were recorded three times by two observers. In addition, in vitro determination of splenic volume was performed using three cadaveric human spleens in a water bath. No statistically significant interobserver or intraobserver variability was present for either two-dimensional or three dimensional ultrasonography. Three-dimensional sonographic estimations of planar splenic volumes and ellipsoid splenic volumes were consistently smaller than two-dimensional sonographic estimations of splenic volumes. Three-dimensional sonographic splenic volumes calculated in vitro using the planar method were accurate to within 2% of in vitro water displacement volumes. Three-dimensional ultrasonography is potentially superior to two-dimensional sonography for evaluation of irregularly shaped objects, such as the spleen, and can provide improved accuracy over that of traditional two-dimensional techniques.  (+info)

The efficacy and limitations of repeated slide conferences for improving interobserver agreement when judging nuclear atypia of breast cancer. The Japan National Surgical Adjuvant Study of Breast Cancer (NSAS-BC) Pathology Section. (18/5805)

BACKGROUND: The pathology section of the Japan National Surgical Adjuvant Study of Breast Cancer protocol study was set up to establish histological criteria for assessing high-risk node-negative breast cancers and standardize the subjective criteria used by collaborating pathologists for nuclear grading of cancers. METHODS: In order to standardize the nuclear atypia criteria, five slide conferences were held. A total of 57 observers assigned nuclear atypia scores to 119 breast carcinomas that were presented using a slide projector or a TV monitor and discussed their histological findings. The percentage interobserver agreements per tumor and per conference and kappa value per conference were estimated and compared among the conferences. The percentage intraobserver reproducibility per tumor between the last two conferences was compared with the percentage interobserver agreement for 20 tumors. The kappa value was also calculated for each of 27 observers to evaluate scoring reproducibility. RESULTS: The percentage interobserver agreement per conference was constant (75-78%) throughout the five meetings and the rate of tumors with > 80% agreement per tumor became higher in later conferences. The kappa value was 0.42, 0.25, 0.42, 0.51 and 0.50 for the first, second, third, fourth and fifth conferences, respectively. The tumors with a lower percentage interobserver agreement also had a lower percentage intraobserver reproducibility and such scoring variations were attributed to the intermediate nature of the degree of tumor atypia. In 26 of 27 observers, intraobserver agreement for 20 tumors was estimated from the kappa value to range from moderate to almost perfect. CONCLUSION: We concluded that the repeated slide conferences conducted by the pathology section were an effective means of standardizing the subjective histopathological criteria used to assess tumors. However, the achievement of a good scoring agreement would be difficult for tumors with an intermediate degree of atypia.  (+info)

Cerebral veins: comparative study of CT venography with intraarterial digital subtraction angiography. (19/5805)

BACKGROUND AND PURPOSE: Our objective was to compare the reliability of CT venography with intraarterial digital subtraction angiography (DSA) in imaging cerebral venous anatomy and pathology. METHODS: In 25 consecutive patients, 426 venous structures were determined as present, partially present, or absent by three observers evaluating CT multiplanar reformatted (MPR) and maximum intensity projection (MIP) images. These results were compared with the results from intraarterial DSA and, in a second step, with the results of an intraobserver consensus. In addition, pathologic conditions were described. RESULTS: Using DSA as the standard of reference, MPR images had an overall sensitivity of 95% (specificity, 19%) and MIP images a sensitivity of 80% (specificity, 44%) in depicting the cerebral venous anatomy. On the basis of an intraobserver consensus including DSA, MPR, and MIP images (415 vessels present), the sensitivity/specificity was 95%/91% for MPR, 90%/100% for DSA, and 79%/91% for MIP images. MPR images were superior to DSA images in showing the cavernous sinus, the inferior sagittal sinus, and the basal vein of Rosenthal. Venous occlusive diseases were correctly recognized on both MPR and MIP images. Only DSA images provided reliable information of invasion of a sinus by an adjacent meningioma. CONCLUSION: CT venography proved to be a reliable method to depict the cerebral venous structures. MPR images were superior to MIP images.  (+info)

Three-dimensional reconstruction of the color Doppler-imaged vena contracta for quantifying aortic regurgitation: studies in a chronic animal model. (20/5805)

BACKGROUND: The purpose of this study was to investigate the use of 3-dimensional (3D) reconstruction of color Doppler flow maps to image and extract the vena contracta cross-sectional area to determine the severity of aortic regurgitation (AR) in an animal model. Evaluation of the vena contracta with 2-dimensional imaging systems may not be sufficiently robust to fully characterize this region, which may be asymmetrically shaped. METHODS AND RESULTS: In 6 sheep with surgically induced chronic AR, 18 hemodynamically different states were studied. Instantaneous regurgitant flow rates were obtained by aortic and pulmonary electromagnetic flowmeters (EMFs) as reference standards, and aortic regurgitant effective orifice areas (EOAs) were determined from EMF regurgitant flow rates divided by continuous-wave (CW) Doppler velocities. Composite video data for color Doppler imaging of the aortic regurgitant flows were transferred into a TomTec computer after computer-controlled 180 degrees rotational acquisition. After the 3D data transverse to the flow jet were sectioned, the smallest proximal jet cross section was identified for direct measurement of the vena contracta area. Peak regurgitant flow rates and regurgitant stroke volumes were calculated as the product of these areas and the CW Doppler peak velocities and velocity-time integrals, respectively. There was an excellent correlation between the 3D-derived vena contracta areas and reference EOAs (r=0.99, SEE=0.01 cm2) and between 3D and reference peak regurgitant flow rates and regurgitant stroke volumes (r=0.99, difference=0.11 L/min; r=0.99, difference=1.5 mL/beat, respectively). CONCLUSIONS: 3D-based determination of the vena contracta cross-sectional area can provide accurate quantification of the severity of AR.  (+info)

Interobserver and intraobserver variations in sonographic measurement of thyroid volume in children. (21/5805)

OBJECTIVE: To determine the interobserver and intraobserver variations in sonographic measurement of thyroid volume in children. DESIGN: Thyroid volumes of 30 healthy children were measured by three separate observers. Additionally each observer measured thyroid volumes of ten separate children three times. METHODS: The data were used to assess intraobserver and interobserver variations in measurement of thyroid volume. Interobserver and intraobserver variations in measuring each diameter of the thyroid gland were also determined. The effect of thyroid size on interobserver and intraobserver variations was analyzed. RESULTS: Intraobserver variation in measurement of thyroid volume was 8.4+/-6.7% (mean+/-s. d.). Interobserver variation was 13.3+/-8.2%. The widest interobserver variation was encountered in determining the craniocaudal diameter of the thyroid gland. No correlation was found between thyroid volume and interobserver variation (r=-0.12, P=0.27), whereas a slight but statistically significant correlation was found between thyroid volume and intraobserver variation (r=-0.26, P=0.012). CONCLUSION: Significant interobserver and intraobserver variation occurs in sonographic measurement of thyroid volume in children.  (+info)

Relationships of fasting and postload glucose levels to sex and alcohol consumption. Are American Diabetes Association criteria biased against detection of diabetes in women? (22/5805)

OBJECTIVE: To compare, in men and women, the prevalence of undiagnosed type 2 diabetes assessed using criteria from the American Diabetes Association (ADA) and the World Health Organization (WHO) and to investigate risk factors associated with fasting and 2-h postload plasma glucose. RESEARCH DESIGN AND METHODS: Data from two companion surveys of Europeans, South Asians, and Afro-Caribbeans in west London were used. A total of 4,367 men and women aged 40-64 years who were not known to have diabetes underwent an oral glucose tolerance test after an overnight fast. The prevalence of undiagnosed diabetes was estimated using the ADA (fasting plasma glucose > or = 7.0 mmol/l) and WHO (2-h postload glucose > or = 11.1 mmol/l) criteria for epidemiologic studies. The association of body fat and usual alcohol intake with plasma glucose and diabetes prevalence was assessed. RESULTS: Compared with the WHO criterion, the ADA criterion gave a higher prevalence of diabetes in men (6.4 vs. 4.7%) but a lower prevalence in women (3.3 vs. 4.2%). In Afro-Caribbeans, the sex difference in diabetes prevalence was reversed. Women had significantly lower fasting glucose than men despite higher 2-h glucose levels. Alcohol intake was positively associated with fasting glucose in men and women but not with 2-h glucose levels. CONCLUSIONS: The new ADA criterion, based on fasting glucose alone, does not take account of sex differences in metabolic response to fasting or possible artifactual effects on fasting glucose. With the ADA criterion, alcohol intake was a significant risk factor for diabetes in our study population; this was not the case with the WHO criterion.  (+info)

Pulmonary venous flow in hypertrophic cardiomyopathy as assessed by the transoesophageal approach. The additive value of pulmonary venous flow and left atrial size variables in estimating the mitral inflow pattern in hypertrophic cardiomyopathy. (23/5805)

AIMS: This study was conducted to assess the characteristics of the pattern of pulmonary venous flow and to document the interaction of this flow and left atrial function with the pattern of mitral inflow in hypertrophic cardiomyopathy. METHODS AND RESULTS: Pulmonary venous and mitral flows were evaluated by the transoesophageal approach in 80 patients with hypertrophic cardiomyopathy. Left atrial size and function were measured by the transthoracic approach. Their values were compared with those obtained from 35 normal controls. Twelve patients showed significant (> 2+) mitral regurgitation. As a group, hypertrophic cardiomyopathy patients showed increased atrial reversal flow and longer deceleration time of the diastolic wave, but a wide variability of pulmonary venous flow patterns were observed. Thirty patients (37.5%) had pseudonormal mitral flow patterns. Stepwise multilinear regression analysis identified the ratio of systolic to diastolic pulmonary venous flow velocity, the ratio of velocity-time integrals of both flow waves at atrial contraction, the left atrial minimal volume and the systolic fraction as independent predictive variables of the mitral E/A wave velocity ratio (r = 0.82). By logistic regression, the former three variables were selected as independent predictive covariates of a pseudonormal mitral flow pattern (sensitivity: 83%, specificity: 90%). The ratio of velocity-time integrals of both atrial waves was the most important predictive variable in both analyses. CONCLUSIONS: The observed variability in the configuration of pulmonary venous flow velocity waveform is related to what occurs in transmitral flow in patients with hypertrophic cardiomyopathy. Significant mitral regurgitation is not an independent correlate of pseudonormal mitral inflow patterns in these patients. Our results further emphasize the complementary, additive value of the pulmonary venous flow velocity pattern and left atrial size in the interpretation of the mitral flow velocity pattern, and indirectly suggest the underlying increased left ventricular filling pressures of patients with hypertrophic cardiomyopathy and pseudonormal mitral flow patterns.  (+info)

An echocardiographic study of right and left ventricular adaptation to physical exercise in elite female orienteers. (24/5805)

BACKGROUND: A considerable body of echocardiographic studies has described how athletic training induces morphological adaptation of the left ventricle in male endurance athletes, but only a few studies have described left ventricular adaptation in female endurance athletes. In contrast to changes in the left ventricle far less attention has been directed towards right ventricular changes due to extensive physical exercise. The purpose of this study was to obtain normal values and to determine if there are any differences in right and left ventricular cavity and wall dimensions between female orienteers and females with a mainly sedentary lifestyle. METHODS: Echocardiography was performed in 42 highly trained elite female orienteers and 32 healthy female students with a predominantly sedentary lifestyle. The 74 females had no history of cardiac disease, a normal electrocardiogram and showed no echocardiographic abnormalities. M-mode and two-dimensional measurements of the right and left ventricular cavity and wall were obtained in elite orienteers and sedentary females. For the right ventricle and wall, multiple cross-sections were used and measurements were obtained from the right ventricular inflow and outflow tract. RESULTS: The left ventricular end-diastolic cavity dimension and the left ventricular wall thickness were significantly greater in the athletes compared with the sedentary controls. The right ventricular inflow tract measurements were all significantly greater in the orienteers compared with the controls but the right ventricular outflow tract measurements were comparable in the study groups. The right ventricular wall thickness, calculated as the mean of three different wall measurements was an average of 13% greater in the athletes compared with the sedentary controls. CONCLUSION: This study suggests symmetrical cardiac enlargement with a concomitant increase in both the right and left ventricular wall, probably reflecting the increased haemodynamic loading in the female athletes.  (+info)