Three-dimensional echocardiography: use of additional spatial data for measuring left ventricular mass.
Explore the source record for details and available documents.
Bias↗
Biomedical subjects
D L King
Publications and source records attributed to D L King.
Rhabdomyolysis with pericardial tamponade.
A young man developed an acute illness and presented to the hospital in shock. On admission, both severe rhabdomyolysis and pericardial tamponade were present, the tamponade occurring as a complication of pericarditis. Echocardiography was required for rapid diagnosis of the cardiac tamponade. The etiology of this severe, life-threatening illness is discussed.
Adolescent↗
Three-dimensional echocardiography. Advances for measurement of ventricular volume and mass.
There is a need for more accurate and reproducible serial measurement of left ventricular volume and mass in individual subjects by echocardiography. Conventional echocardiography has significant measurement variability because of its use of geometric assumptions and image plane positioning errors. Guided three-dimensional echocardiography eliminates geometric assumptions and reduces image plane positioning errors by using a "line of intersection" display. Use of three-dimensional guided imaging for a one-dimensional measurement of the left ventricle resulted in a threefold improvement of interobserver variability over conventional echocardiographic measurements. Computer-aided three-dimensional reconstruction of the ventricle for ventricular volume from a series of 8 to 10 short-axis images also achieved more than a threefold improvement of interobserver variability compared with two-dimensional echocardiography. Three-dimensional echocardiographic computation of ventricular volume and mass in healthy subjects was achieved with an accuracy comparable to magnetic resonance imaging and was superior to two-dimensional echocardiography. Three-dimensional echocardiography promises to be a more accurate method of estimating left ventricular volume and mass and may be suitable for serial study of individual subjects because of its improved accuracy and decreased interobserver variability compared with conventional echocardiographic methods.
Diastole↗
Aortic valve papillary fibroelastoma. A diagnosis by transthoracic echocardiography.
Cardiac papillary fibroelastomas are unusual, frond-like growths typically found on cardiac valves, diagnosed incidentally on autopsy or cardiac surgery, but rarely during life. We report a rare case of an aortic valve papillary fibroelastoma detected by transthoracic echocardiography and confirmed by histologic study.
Aortic Valve↗
Sudden death due to coronary artery anomalies: a case report and clinical review.
Congenital anomalies of the coronary arteries are relatively uncommon conditions with an incidence of approximately 2% in the adult population. Although less common than acquired coronary artery disease, these anomalies may be associated with myocardial ischemia and its consequences; angina, arrhythmia, infarction, and sudden death. A 21-year-old female patient with no significant prior medical history was found dead at home. Postmortem examination revealed high take-off of the right coronary artery with acute down-ward angulation of the proximal right coronary artery and acute downward angulation of the left main coronary artery. Microscopic examination revealed global myocardial ischemia consistent with a terminal ventricular dysrhythmia. There was no evidence of any other disease processes. Detailed toxicological investigation was negative. The Regional Forensic Pathology Unit experience with sudden death due to congenital coronary artery anomalies is presented along with a review of the current literature.
Adult↗
Three-dimensional echocardiographic measurement of left ventricular volume in vitro: comparison with two-dimensional echocardiography and cineventriculography.
OBJECTIVES: This study was designed to compare three-dimensional echocardiography, two-dimensional echocardiography and cineventriculography for the purpose of measuring left ventricular volume in vitro. BACKGROUND: Three-dimensional echocardiographic systems have been shown to be highly accurate in measuring the volumes of balloon phantoms. However, three-dimensional techniques have not been compared with standard two-dimensional echocardiography in vitro or with cineventriculography, the clinical standard for left ventricular volume measurement. METHODS: Excised porcine hearts were prepared with an internal latex sheath that could be filled and maintained with a known ("true") volume of liquid. Each heart was then imaged by cineventriculography, standard two-dimensional echocardiography and three-dimensional echocardiography. Left ventricular volumes were calculated from 15 hearts at 25 volumes ranging from 50 to 280 ml by the following methods: 1) biplane cineventriculography using the area-length method; 2) two-dimensional echocardiography by the apical biplane method using a summation of discs algorithm in 15 cases and the single-plane, four-chamber method using a summation of discs algorithm in 10 cases; and 3) three-dimensional echocardiography using a polyhedral surface reconstruction volume computation algorithm based on multiple nonparallel, nonevenly spaced short-axis cross sections. RESULTS: Results were compared with true volume, and a nonparametric analysis of variance was performed. Both measurement bias (systematic error) and imprecision (random error) were assessed. All methods tended to underestimate the true volume (two-dimensional echocardiography -6.1 +/- 17.6%, three-dimensional echocardiography -4.7 +/- 5.0% and biplane cineventriculography -3.9 +/- 8.2%), although differences were not significant. Although there was a significant correlation between the magnitude of measurement bias and the size of the volume being measured for two-dimensional echocardiography and cineventriculography, the bias of three-dimensional echocardiography was fairly constant over the range of volumes. When bias was accounted for, two-dimensional echocardiography was significantly less precise than cineventriculography and three-dimensional echocardiography in terms of percent error (15.3 +/- 11.9%, 5.6 +/- 5.7% and 3.9 +/- 3.4%, respectively). CONCLUSIONS: Three-dimensional echocardiography using a polyhedral surface reconstruction algorithm for volume computation provides accuracy comparable to that of biplane cineventriculography in this in vitro model. Standard two-dimensional echocardiographic volume computation is significantly less accurate than the other two methods.
Algorithms↗
A Drosophila single-strand DNA/RNA-binding factor contains a high-mobility-group box and is enriched in the nucleolus.
We have isolated a Drosophila melanogaster cDNA encoding a high-mobility-group (HMG) box-containing protein. This protein shares 50% amino acid identity with the human putative structure-specific recognition protein, hSSRP. The gene encoding the D. melanogaster homolog, DssRP, is developmentally regulated and is expressed most abundantly in ovaries (nurse cells in particular). The protein is localized in nuclei and is particularly abundant in the nucleolus. In vitro binding studies using DssRP produced in bacteria showed that, despite expectation, the protein does not bind to structured DNA. Instead, it binds to single-stranded DNA and RNA, with highest affinity to nucleotides G and U.
Amino Acid Sequence↗
Context-produced increase in visibility.
UNLABELLED: It has not been clearly shown that context (e.g., three lines of a square) increases the visibility of a feature (e.g., the fourth line of the same square). To investigate this possibility, four sets of context+feature, context, feature, and BLANK (empty field) stimuli were used. For three out of the four sets, the context+feature stimulus was less likely to be falsely identified as the context and BLANK stimuli (i.e., the stimuli without the feature) than was the feature stimulus. For the same three sets, discriminating between the context+feature and context stimuli produced fewer false identifications (FIs) than discriminating between the feature and BLANK stimuli. THE CONCLUSION: the context components of context+feature stimuli increased the visibility of the feature components of the same stimuli.
Attention↗
Left ventricular volume and endocardial surface area by three-dimensional echocardiography: comparison with two-dimensional echocardiography and nuclear magnetic resonance imaging in normal subjects.
OBJECTIVES: We evaluated a three-dimensional echocardiographic method for ventricular volume and surface area determination that uses polyhedral surface reconstruction. Six to eight nonparallel, unequally spaced, nonintersecting short-axis planes were positioned with a line of intersection display to overcome limitations associated with two-dimensional echocardiography. BACKGROUND: Two-dimensional echocardiographic methods of ventricular volume and surface area determination are limited by assumptions about ventricular shape and image plane position. METHODS: Left ventricular end-diastolic and end-systolic volumes and endocardial surface areas determined by three-dimensional echocardiography and nuclear magnetic resonance (NMR) imaging were compared in 15 normal subjects (7 men, 8 women, aged 23 to 41 years, body surface area 1.38 to 2.17 m2). Ten of these subjects also underwent two-dimensional echocardiography; and end-diastolic and end-systolic volumes were determined by the apical biplane summation of discs method and compared with results of NMR imaging. RESULTS: Interobserver variability was 5% to 8% for three-dimensional echocardiography and 6% to 9% for NMR imaging. Both methods were in close agreement on end-diastolic volume (r = 0.92, SEE = 6.99 ml) and end-systolic volume (r = 0.81, SEE = 4.01 ml) and on end-diastolic surface area (r = 0.84, SEE = 8.25 cm2) and end-systolic surface area (r = 0.84, SEE = 4.89 cm2). Three-dimensional echocardiography and NMR imaging correlated significantly better for end-diastolic volume (r = 0.90, SEE = 7.0 ml) and end-systolic volume (r = 0.88, SEE = 3.1 ml) than did two-dimensional echocardiography and NMR imaging (r = 0.48, SEE = 20.5 ml for end-diastolic volume; r = 0.70, SEE = 5.6 ml for end-systolic volume). CONCLUSIONS: Three-dimensional echocardiography is an in vivo method of measuring left ventricular end-diastolic and end-systolic volumes and endocardial surface area with results comparable to those of NMR imaging. Additionally, three-dimensional echocardiography is superior to the two-dimensional echocardiographic apical biplane summation method because the technique eliminates geometric assumptions and image plane positioning error.
Adult↗
A dominant-subordinate unit-against-unit theory of decreases in visibility.
When simultaneous stimuli or stimuli in metacontrast and related research are perceived (recognized, apprehended) as two different phenomenal groups (wholes, things), the visibility of the group with less intense, smaller, no-onsetting, terminating, and briefer features decreases. This decrease also occurs when one of two groups with equally intense, etc. features is made less visible through masking. Therefore, the relative visibility of two groups predicts a decrease in the visibility of one of them better than does their relative intensity, etc. Further, (1) the visibility of all the parts (perceived features, attributes) of both groups is similarly affected, so each group functions as one entity and (2) decreases in visibility are eliminated when stimuli produce only one group. The theory: a neural unit underlies the perception of one group and its parts, and two such units underlie the perception of two groups and their parts (one unit for each group). In addition, the unit for a dominant (high visibility) group inhibits the unit for a subordinate (low visibility) group, thereby decreasing the visibility of the subordinate group. Also, when stimuli produce only one group (hence one unit), unit-against-unit inhibition and hence a decrease in visibility is precluded.
Contrast Sensitivity↗
Two effects of context on the presence/absence of connecting segments.
Stimulus A consisted of two proximal brackets with colinear lines separated by small gaps. Stimulus B was a square-like rectangle produced by inserting connecting segments into the gaps. Stimulus A was frequently represented as B (i.e., as closed). Following Pomerantz and Pristach (1989) and Treisman and Paterson (1984), perhaps A produced a closure emergent feature that was salient but otherwise independent of other features. However, adding the same two vertical lines (context) to both A and B produced a contrasting division outcome, even though the putative closure emergent feature was an element of the A+context stimulus, and even though it matched a physical feature of the B+context stimulus. Therefore, this emergent feature did not produce the closure. Two additional experiments indicated that the two context lines made the two connecting segments more visible--a context-produced increase in visibility occurred that is not comparable to other known evidence of perceptual improvement. This greater visibility also indicates that the division was not due to the two context lines inhibiting the perception of the two connecting segments, and the closure was not due to good continuation.
Contrast Sensitivity↗
Three-dimensional echocardiography.
Lack of spatial registration of imaging transducers is a major technical limitation of two-dimensional (2-D) echocardiography. Volume scanning of the heart, or three-dimensional (3-D) echocardiography, is achieved by using a 3-D spatial registration device with a conventional 2-D scanner, or by using a high speed, phased-array real-time scanner. Three-dimensional spatial coordinate systems may be external or internal systems with respect to the scanning transducer. With external systems data acquired from several cardiac windows may be integrated and reconstructed. An external coordinate system allows creation of a "line of intersection" display to guide image positioning in the nonvisualized dimension orthogonal to the real-time image. Use of this display has shown a significant, threefold improvement in the accuracy of image positioning and the reproducibility of chamber measurements. Three-dimensional echocardiography using polyhedral surface reconstruction also yields more accurate measurement of ventricular volume and new measurements of total endocardial surface area and infarct surface area. Computer modeling and 3-D computergraphic displays hold promise of valuable new methods of communication, data analysis, and surgical planning.
Cardiac Volume↗
DNA binding and heteromerization of the Drosophila transcription factor chorion factor 1/ultraspiracle.
The Drosophila chorion factor 1/ultraspiracle (CF1/USP) transcription factor, a homologue of the retinoid X receptor, is a developmentally important member of the family of nuclear (steroid) hormone receptors. Using newly developed monoclonal antibodies and a full-length bacterially produced protein, we have studied in detail the in vitro DNA-binding properties of this factor and aspects of its distribution in vivo. During oogenesis, CF1/USP is present both in germline cells and in the somatic follicular epithelium. We have determined the optimal binding site of partially purified bacterially produced CF1/USP by an in vitro selection procedure and also have characterized its binding to the follicular-specific chorion s15 promoter. In vitro this bacterially produced factor is unusual in binding to a single element ("half-site"); simultaneous but noncoordinate binding to a second half-site is possible if these repeated elements are organized in direct orientation and spaced adequately. However, the factor interacts synergistically with several other nuclear hormone receptors: notably, it can form in vitro heteromers with mammalian thyroid and retinoic acid receptors, binding to two half-sites that are organized in either direct or inverted orientation. In vivo the factor most probably functions as a heterodimer, but its partner(s) remains to be determined.
Animals↗
Improved reproducibility of left atrial and left ventricular measurements by guided three-dimensional echocardiography.
OBJECTIVES: The objective of this study was to determine whether guided three-dimensional echocardiography could improve the reproducibility of left atrial and left ventricular anteroposterior measurements over that of standard unguided two-dimensional echocardiography. BACKGROUND: Although these measurements are standard indexes for evaluating chamber size, their use is limited by significant interobserver variability largely due to variable image plane positioning. To improve measurement accuracy and reproducibility, we have developed a three-dimensional echocardiograph that displays the line of intersection of the real-time image with a previously saved orthogonal reference image. This display shows the relation of the real-time image to anatomic landmarks in its third, nonvisualized dimension and may be used to guide image positioning. METHODS: Three pairs of operators independently performed unguided two-dimensional and guided three-dimensional examinations on three groups of 10 patients each. The left atrium was measured in a plane through the inferior surface of the aortic cusps and the left ventricle in a plane perpendicular to its long axis 1 cm below the mitral leaflet tips. Interobserver variability of these measurements on unguided parasternal long-axis images and on guided short-axis images was assessed. RESULTS: The standard unguided two-dimensional examination was associated with an interobserver variability of 14.6% and 9.1% for atrial and ventricular measurements, respectively. Guided three-dimensional echocardiography significantly reduced interobserver variability to 5.0% and 3.1%, respectively, for the same measurements (p < 0.005 by McNemar's test). CONCLUSIONS: Significant interobserver variability occurs with standard unguided two-dimensional echocardiographic measurement of left atrial and left ventricular dimensions. Guided three-dimensional echocardiography achieves a nearly threefold improvement of reproducibility of these measurements and provides the basis for improved serial evaluation and comparison of atrial and ventricular size by different operators.
Adult↗
Amelioration of mitral valve prolapse after treatment for panic disorder.
Twenty panic disorder patients with mitral valve prolapse showed amelioration of prolapse on repeat echocardiogram after treatment for panic disorder. This effect was significant when compared to repeat echocardiograms in eight psychiatrically normal control subjects with mitral valve prolapse.
Adult↗
The effect of the size of one and two traffic signs on two measures of perceptual performance.
A large object can delay the perception of a small object, which hints that the use of larger objects in general and larger traffic signs in particular may be counterproductive. The present study employed either one traffic sign or two contiguous traffic signs on a post in a photograph of a road scene. Identification of a small target sign was not slower when a second sign was contiguous than when there was only the one small target sign, regardless of whether the contiguous sign was large or small. Furthermore, when a counting task was used with the same stimuli, a large sign accelerated the response to two-sign stimuli, again regardless of the contiguous sign's size. In addition, the response to two-sign stimuli was not slower than the response to one-sign stimuli. The large small comparisons of both experiments reduce the concern that employing a large traffic sign will delay the perception of a second contiguous sign. Moreover, the one-two comparisons of both experiments imply that employing two contiguous signs will not delay the perception of a sign, despite widespread evidence that a nearby object will delay the perception of a target object.
Adult↗
Evaluation of in vitro measurement accuracy of a three-dimensional ultrasound scanner.
We have constructed a three-dimensional (3-D) ultrasound scanner to make examinations easier and more accurate. The accuracy of the 3-D scanner has been determined by scanning a three-dimensional model. Lengths, angles, and volume of the model were computed and compared to values determined from physical measurement. Distances between image planes were computed with a mean error of 0.4% of true value. Volume was computed with a mean error of 1.6%, or 0.64 mL +/- 0.72 mL (1 SD). We conclude that the 3-D scanner has a system error of less than 0.4%, that it does not introduce significant new errors, and that the principal source of measurement error is poor lateral resolution due to ultrasound beam width. We believe that the 3-D scanner may be a clinically useful instrument for quantitative echographic measurements.
Algorithms↗
The chorion genes of the medfly, Ceratitis capitata, I: Structural and regulatory conservation of the s36 gene relative to two Drosophila species.
We have used low stringency screening with the Drosophila melanogaster s36 chorion gene to recover its homologue from genomic and cDNA libraries of the medfly, Ceratitis capitata. The same gene has also been recovered from a genomic library of D. virilis. The medfly s36 gene shows similar developmental specificity as in Drosophila (early choriogenesis). It is also specifically amplified in ovarian follicles; this is the first report of chorion gene amplification outside the genus Drosophila. Alignments of s36 sequences from three species show that, in addition to its regulatory conservation, the s36 gene is extensively conserved in sequence, in a region corresponding to a central protein domain, and in short regions of 5' flanking DNA that might correspond to cis-regulatory elements.
Amino Acid Sequence↗