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Girdauskas E, Kempfert J, Kuntze T, Holubec T, Krane M, Borger M, Eden M, Bramlage P, Pausch J, Gross TMS, Müller L, Reichenspurner H. Standardized Subannular Repair for Treatment of Secondary Mitral Regurgitation: Initial Results from the Reform-MR Registry. Thorac Cardiovasc Surg 2021. [DOI: 10.1055/s-0041-1725719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Eden M, Tompkins J, Verheijde J. Reliability and validity of functional performance assessments in patients with head and neck cancer. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Langer C, Both M, Harders H, Lutz M, Eden M, Kühl C, Sattler B, Jansen O, Schaefer P, Frey N. Late enhanced computed tomography in Hypertrophic Cardiomyopathy enables accurate left-ventricular volumetry. Eur Radiol 2014; 25:575-84. [PMID: 25316053 DOI: 10.1007/s00330-014-3434-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/22/2014] [Accepted: 09/04/2014] [Indexed: 01/19/2023]
Abstract
OBJECTIVES Late enhancement (LE) multi-slice computed tomography (leMDCT) was introduced for the visualization of (intra-) myocardial fibrosis in Hypertrophic Cardiomyopathy (HCM). LE is associated with adverse cardiac events. This analysis focuses on leMDCT derived LV muscle mass (LV-MM) which may be related to LE resulting in LE proportion for potential risk stratification in HCM. METHODS N=26 HCM-patients underwent leMDCT (64-slice-CT) and cardiovascular magnetic resonance (CMR). In leMDCT iodine contrast (Iopromid, 350 mg/mL; 150mL) was injected 7 minutes before imaging. Reconstructed short cardiac axis views served for planimetry. The study group was divided into three groups of varying LV-contrast. LeMDCT was correlated with CMR. RESULTS The mean age was 64.2 ± 14 years. The groups of varying contrast differed in weight and body mass index (p < 0.05). In the group with good LV-contrast assessment of LV-MM resulted in 147.4 ± 64.8 g in leMDCT vs. 147.1 ± 65.9 in CMR (p > 0.05). In the group with sufficient contrast LV-MM appeared with 172 ± 30.8 g in leMDCT vs. 165.9 ± 37.8 in CMR (p > 0.05). Overall intra-/inter-observer variability of semiautomatic assessment of LV-MM showed an accuracy of 0.9 ± 8.6 g and 0.8 ± 9.2 g in leMDCT. All leMDCT-measures correlated well with CMR (r > 0.9). CONCLUSIONS LeMDCT primarily performed for LE-visualization in HCM allows for accurate LV-volumetry including LV-MM in > 90% of the cases. KEY POINTS • LeMDCT of relatively low contrast allows for LV planimetry in HCM. • The correlation of leMDCT-based LV volumetry with gold-standard CMR was excellent (r > 0.9). • LeMDCT requires approximately 2.0mL/kgBW of dye to achieve acceptable contrast.
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Affiliation(s)
- Christoph Langer
- Department of Cardiology, Angiology and Critical Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Christian-Albrechts-Universität Kiel, Schittenhelmstr. 12, 24105, Kiel, Germany,
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Langer C, Hohnhorst M, Schaefer P, Lutz M, Luedde M, Eden M, Kuehl C, Prinz C, Faber L, Frey N. Cardiac CT in hypertrophic cardiomyopathy: volumetric assessment of intramyocardial fibrosis. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p4709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Eden M, Köhl-Hackert N, Krautter M, Jünger J, Nikendei C. An innovative model for the structured on-ward supervision of final year students. Med Teach 2010; 32:181. [PMID: 20163239 DOI: 10.3109/01421591003656867] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Abstract
The standard interpolation approach to image resizing is to fit the original picture with a continuous model and resample the function at the desired rate. However, one can obtain more accurate results if one applies a filter prior to sampling, a fact well known from sampling theory. The optimal solution corresponds to an orthogonal projection onto the underlying continuous signal space. Unfortunately, the optimal projection prefilter is difficult to implement when sine or high order spline functions are used. We propose to resize the image using an oblique rather than an orthogonal projection operator in order to make use of faster, simpler, and more general algorithms. We show that we can achieve almost the same result as with the orthogonal projection provided that we use the same approximation space. The main advantage is that it becomes perfectly feasible to use higher order models (e.g. splines of degree n=or>3). We develop the theoretical background and present a simple and practical implementation procedure using B-splines. Our experiments show that the proposed algorithm consistently outperforms the standard interpolation methods and that it provides essentially the same performance as the optimal procedure (least squares solution) with considerably fewer computations. The method works for arbitrary scaling factors and is applicable to both image enlargement and reduction.
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Affiliation(s)
- C Lee
- Department of Electronic Engineering, Yonsei University, Seoul, Korea.
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Unser M, Aldroubi A, Eden M. Enlargement or reduction of digital images with minimum loss of information. IEEE Trans Image Process 1995; 4:247-258. [PMID: 18289976 DOI: 10.1109/83.366474] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The purpose of this paper is to derive optimal spline algorithms for the enlargement or reduction of digital images by arbitrary (noninteger) scaling factors. In our formulation, the original and rescaled signals are each represented by an interpolating polynomial spline of degree n with step size one and Delta, respectively. The change of scale is achieved by determining the spline with step size Delta that provides the closest approximation of the original signal in the L(2)-norm. We show that this approximation can be computed in three steps: (i) a digital prefilter that provides the B-spline coefficients of the input signal, (ii) a resampling using an expansion formula with a modified sampling kernel that depends explicitly on Delta, and (iii) a digital postfilter that maps the result back into the signal domain. We provide explicit formulas for n=0, 1, and 3 and propose solutions for the efficient implementation of these algorithms. We consider image processing examples and show that the present method compares favorably with standard interpolation techniques. Finally, we discuss some properties of this approach and its connection with the classical technique of bandlimiting a signal, which provides the asymptotic limit of our algorithm as the order of the spline tends to infinity.
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Affiliation(s)
- M Unser
- Nat. Center for Res. Resources, Nat. Inst. of Health, Bethesda, MD
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Unser M, Eden M. Nonlinear operators for improving texture segmentation based on features extracted by spatial filtering. ACTA ACUST UNITED AC 1990. [DOI: 10.1109/21.105080] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Unser M, Pelle G, Brun P, Eden M. Automated extraction of serial myocardial borders from M-mode echocardiograms. IEEE Trans Med Imaging 1989; 8:96-103. [PMID: 18230505 DOI: 10.1109/42.20367] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A method is presented for the automated extraction of myocardial borders in M-mode echocardiograms. The successive steps of processing are: preprocessing for noise reduction, enhancement of border characteristics using a set of suitably chosen matched filters, and final extraction of border points by searching for optimal paths along the time axis. During the last step of processing, the contribution of each elementary border element is characterised by a normalized correlation coefficient. The optimal path, defined as the one that maximizes the sum of all elementary contributions, is determined efficiently using dynamic programming. An alternative approach uses a maximum tracking procedure whose performances are improved by utilizing a local model to predict the position of the next border point. Experimental examples are presented and the performance of both border extraction algorithms are compared.
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Affiliation(s)
- M Unser
- Nat. Inst. of Health, Bethesda, MD
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Eden M. Anatomy, physiology, chemistry, and image processing. Boll Soc Ital Biol Sper 1988; 64:5-26. [PMID: 3077916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Unser M, Ellis JR, Pun T, Eden M. Optimal background estimation in EELS. J Microsc 1987; 145:245-56. [PMID: 3585991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In quantitative electron energy loss spectrometry, it is desirable to estimate the background law below core edge energy in a way that provides the maximum signal-to-noise ratio. Assuming an inverse power background model and independently Poisson distributed measurements, it is shown how to achieve this goal by using a maximum likelihood (ML) estimation technique which provides unbiased and minimum mean square error estimates of all parameters of interest. An efficient and computationally stable implementation of this procedure is proposed. Standard logarithmic least squares estimations are then compared with the ML approach and the gain in performance due to optimal processing is quantified.
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Eden M. Smart instruments, microprocessors, and personal computers. Int J Technol Assess Health Care 1986; 3:319-25. [PMID: 10284929 DOI: 10.1017/s0266462300000611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This discussion of Emerging Technology focuses on technological currents in electronic technology rather than in medical technology per se. The influence of the former on the latter is not merely that medical devices have electronic parts, but that the development of new circuit technology can change radically the design, utility, and even the function of the medical devices.
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Schuette WH, Carducci E, Marti GE, Shackney SE, Eden M. The relationship between mean channel selection and the calculated coefficient of variation. Cytometry 1985; 6:487-91. [PMID: 4042790 DOI: 10.1002/cyto.990060515] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Calculated coefficients of variation (CV) taken from the quotient of the standard deviation (S.D.) and the mean value of measured distributions are often used as an indicator of system performance in linear flow cytometry (FCM). The ability of the calculated CV to estimate the true CV of the underlying experiment before grouping (channelization) is dependent on the relationship between the width of the data channels and the magnitude of the S.D. of the measured distribution. When the channel width is equal to the S.D. of a distribution, the calculated CV is approximately 20% larger than the true CV of an experiment. By the time the S.D. is only one-half of a channel width, the calculated CV is unreliable. When the distribution S.D. is narrower than a channel's width, small changes in the distribution mean value will cause large variations in the calculated CV. As the true CV decreases, the calculation must be made with higher mean channel values. This dependence of calculated CV accuracy upon the relationship between S.D. and channel width places limitations upon mean channel selection that must be considered when using CV calculations for evaluating system performance, especially when looking for small improvements during optical alignment procedures. When an instrument is assumed to have a constant CV and the data are collected linearly, it is possible to improve the CV estimation accuracy by placing distributions in higher-numbered channels.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
In quantitative Electron Energy Loss Spectrometry, a weighted least squares estimation should theoretically be used to estimate the background law below core edge energy, since the variances of the data vary. However, it is found that proper weighting makes the above edge signal-to-noise ratio decrease rather than increase. This result is discussed, and the influence of the bias introduced by the logarithmic transformation of the data is quantified.
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Abstract
Optimizing the acquisition parameters for EELS recording has to be accomplished simultaneously from the physical and the statistical points of view; the statistical aspect of the question is covered here. Approximate probability density functions of the variables of interest are derived, which provide a global measure of signal-to-noise ratio taking into account every step of the EELS edge area estimation process. Qualitative and quantitative advice is given regarding the critical choice of the estimation and integration energy regions. The notion of visual contrast is presented; it permits the introduction of the concept of statistical detection limit. It is found that for typical experimental conditions, when other factors are equal, the required analysis time for the sample varies approximately as the inverse square of the concentration.
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Abstract
The proper analysis of positron emission tomographic scan data requires a careful knowledge of the limitations of the tomographic system used so that scan data can be collected and sampled in a manner consistent with those limitations. The present investigation was undertaken to clarify some of the limitations imposed by resolution. The usual imaging situation, e.g., 218FDG , C15O2, or 15O2 , involves imaging structures of limited size in all three dimensions which may appear either warm or cool in relation to some background level of activity. In emission tomography the importance of adequate data sampling within a given plane has been frequently emphasized. Little attention, however, has been given to proper z axis sampling for clinical scanning. The actual selection of regions of interest from scans can have a significant impact on the subsequent statistical analysis. Previous work on this subject has experimentally examined the relationship of object size to quantitative estimation in the hot spot-cold background situation for the one- and two-dimensional cases. Approximate three-dimensional recovery coefficients for the hot spot-cold background situation have been calculated. An examination of the factors discussed above, three-dimensional objects with varying contrast, z axis sampling, and selection of regions of interest, has not yet been addressed in the literature. The purpose of the present investigation is to examine these factors.
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Bell E, Marek LF, Merrill C, Levinstone DS, Young T, Eden M, Sher S. Loss of Division Potential in Culture: Aging or Differentiation? Science 1980; 208:1483. [PMID: 17796697 DOI: 10.1126/science.208.4451.1483] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Bell E, Levinstone D, Sher S, Marek L, Merrill C, Young I, Eden M. An interactive computer system for the analysis of cell lineages. J Histochem Cytochem 1979; 27:458-62. [PMID: 374610 DOI: 10.1177/27.1.374610] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We have developed an interactive computer system for analysing cell lineage data. It can be utilized in studies of cell motility, cell division, cell differentiation, and cell aging. It has enabled us to document the heterogeneity of human foreskin fibroblasts in culture and to propose that loss of proliferative potential may mean that cells enter a state of differentiation which makes them unable to respond to mitotic stimulation. Our method, which enables us to apply immunological and cytochemical probes after recording the history of a cell lineage, should allow us to define precisely features which uniquely distinguish cycling from noncycling cells on an individual cell basis.
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Abstract
We have examined the hypothesis that diploid cells grown in vitro age, and propose that only proliferative potential and not life-span is telescoped. We suggest that explanted or transplanted diploid cells are driven to divide by the process of subculturing in vitro or in vivo and, in response to this pressure, also complete their differentiation and become refractory to further mitotic stimulation. We conclude that differentiation rather than "mortality" distinguishes diploid from transformed cells and that the former may not age in vitro, but are lost because culture methods are selective for cycling cells.
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Abstract
A new approach to a system for chromosome karyotyping is presented. The system assembles the information about chromosomes from several cells at a time, thereby filtering out noise due to variations in the slide preparations. The system makes i possible to use metaphase spreads which are incomplete due to missing chromosomes, touching and overlapping chromosomes and stain particles. The system gives a precise description of the chromosome complement in terms of distribution function parameters, with the uncertainty of the parameters specificed. The system is adaptive with respect to the initial reference parameter set so that both recognition of normal chromosomes, in spite of the variation displayed among individuals, and identification of aberrant chromosomes are possible. The precise chromosome descriptors can be used to detect differences between the tested individual and various references, in order to find chromosomal abnormalities.
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Blesser B, Shillman R, Kuklinski T, Cox C, Eden M, Ventura J. A theoretical approach for character recognition based on phenomenological attributes. ACTA ACUST UNITED AC 1974. [DOI: 10.1016/s0020-7373(74)80033-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Eden M, Green JE, Sun A. Feasibility of computer screening of blood films for the detection of malaria parasites. Bull World Health Organ 1973; 48:211-8. [PMID: 4578363 PMCID: PMC2481007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
This paper considers the feasibility of automatic screening procedures for detecting malaria parasites in blood smears prepared in the field. A simple programme for pattern recognition by computer has been developed for thin blood films that identifies parasites as densely stained particles within an erythrocyte. The parasites are detected correctly, but platelets falling accidentally within the outline of an erythrocyte and perhaps reticulocytes may be wrongly classified as parasites. The results indicate that automated detection of parasites is technically feasible but that the technique needs to be refined to reduce the incidence of false positives. A substantial increase in processing speed is required if the automatic procedure is to be economically feasible in screening programmes. The complexity of the equipment and the need for well prepared blood smears point to a possible use of the technique in laboratory checks but not under usual field conditions.
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Eden M. Image processing techniques in relation to studies of red cell shape. Nouv Rev Fr Hematol 1972; 12:861-9. [PMID: 4268795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Eden M, Bates R. Resolution of the dissociation constants of d,l-malic acid from 0-degrees-c to 50-degrees-c. J Res Natl Bur Stand (1977) 1959. [DOI: 10.6028/jres.062.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Bates R, Diamond P, Eden M, Acree S. Salt effects of potassium nitrate, sodium sulfate, and trisodium citrate on the activity coefficients of p-phenolsulfonate buffers. J Res Natl Bur Stand (1977) 1946. [DOI: 10.6028/jres.037.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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