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Image Interpretation (image + interpretation)

Distribution by Scientific Domains
Medical Sciences85%

Selected Abstracts

Diagnosis of middle phalanx bone marrow lesions in horses using magnetic resonance imaging and identification of phase effect cancellation for proper image interpretation

EQUINE VETERINARY EDUCATION, Issue 3 2009
N. Werpy
First page of article [source]

Neccesity for Standardization in Fluorescence Pattern Analysis

IMAGING & MICROSCOPY (ELECTRONIC), Issue 1 2009
Petra Perner Dr.
Fluorescent pattern analysis is used in cellular and molecular biology as well as in medicine, agriculture or other applications. To make it feasible in daily practice, standardization is necessary to obtain authentically and reproducible results. Standardization has many aspects (fig. 1). It has to do with sample preparation, imaging techniques, knowledge acquisition, and image interpretation. It is an iterative process and cannot be solved from scratch. [source]

Challenges to interpretation of breast MRI

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2001
Karen Kinkel MD
Abstract This review describes the current knowledge and challenges of lesion interpretation with MRI of the breast according to different image interpretation strategies. Particular emphasis is given to patient- and tumor-related factors that influence image interpretation. The impacts of the menstrual cycle, prior surgery, radiation therapy, and chemotherapy are summarized. Particular enhancement features of ductal carcinoma in situ (DCIS) or invasive lobular carcinoma are described. Finally, an adequate diagnosis at MRI of the breast should take into account the results of the patient's history, physical examination, and all imaging tests performed before MRI. J. Magn. Reson. Imaging 2001;13:821,829. © 2001 Wiley-Liss, Inc. [source]

Quantitative sodium imaging with a flexible twisted projection pulse sequence

MAGNETIC RESONANCE IN MEDICINE, Issue 6 2010
Aiming Lu
Abstract The quantification of sodium MR images from an arbitrary intensity scale into a bioscale fosters image interpretation in terms of the spatially resolved biochemical process of sodium ion homeostasis. A methodology for quantifying tissue sodium concentration using a flexible twisted projection imaging sequence is proposed that allows for optimization of tradeoffs between readout time, signal-to-noise ratio efficiency, and sensitivity to static field susceptibility artifacts. The gradient amplitude supported by the slew rate at each k -space radius regularizes the readout gradient waveform design to avoid slew rate violation. Static field inhomogeneity artifacts are corrected using a frequency-segmented conjugate phase reconstruction approach, with field maps obtained quickly from coregistered proton imaging. High-quality quantitative sodium images have been achieved in phantom and volunteer studies with real isotropic spatial resolution of 7.5 × 7.5 × 7.5 mm3 for the slow T2 component in ,8 min on a clinical 3-T scanner. After correcting for coil sensitivity inhomogeneity and water fraction, the tissue sodium concentration in gray matter and white matter was measured to be 36.6 ± 0.6 ,mol/g wet weight and 27.6 ± 1.2 ,mol/g wet weight, respectively. Magn Reson Med 63:1583,1593, 2010. © 2010 Wiley-Liss, Inc. [source]

Phase-sensitive cardiac tagging,REALTAG

MAGNETIC RESONANCE IN MEDICINE, Issue 1 2007
J. Andrew Derbyshire
Abstract Fully inverting spins, instead of merely saturating them, provides superior contrast for tagging procedures. The resulting improvement in tag contrast-to-noise ratio (CNR) yields higher-precision tag detection. Also, thinner slices and hence reduced tag separations can be employed, providing displacement and strain measurements with better spatial resolution. Alternatively, the improved tag contrast can be used to obtain cine images covering a greater portion of the cardiac cycle. The use of standard magnitude reconstruction for images of these inversion tags causes rectification of the negative-valued signals from the tags, confounding the image interpretation. Therefore, a phase-sensitive reconstruction scheme of the inverted tags must be employed. Here we demonstrate the implementation of inverted tags with phase-sensitive reconstruction in a ramped-flip-angle, steady-state free precession (SSFP) sequence. Magn Reson Med 58:206,210, 2007. © 2007 Wiley-Liss, Inc. [source]

Patient gender and radiopharmaceutical tracer is of minor importance for the interpretation of myocardial perfusion images using an artificial neural network

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2006
Kristina Tägil
Summary The purpose of this study was to assess the influence of patient gender and choice of perfusion tracer on computer-based interpretation of myocardial perfusion images. For the image interpretation, an automated method was used based on image processing and artificial neural network techniques. A total of 1000 patients were studied, all referred to the Royal Brompton Hospital in London for myocardial perfusion scintigraphy over a period of 1 year. The patients were randomized to receive either thallium or one of the two technetium tracers, methoxyisobutylisonitrile or tetrofosmin. Artificial neural networks were trained with either mixed gender or gender-specific and mixed tracer or tracer-specific training sets of different sizes. The performance of the networks was assessed in separate test sets, with the interpretation of experienced physicians regarding the presence or absence of fixed or reversible defects in the images as the gold standard. The neural networks trained with large mixed gender training sets were as good as the networks trained with gender-specific data sets. In addition, the neural networks trained with large mixed tracer training sets were as good as or better than the networks trained with tracer-specific data sets. Our results indicate that the influence of patient gender and perfusion tracer are of minor importance for the computer-based interpretation of the myocardial perfusion images. The differences that occur can be compensated for by larger training sets. [source]

Configuration and timing of Ungava Bay ice streams, Labrador,Ungava, Canada

BOREAS, Issue 1 2003
KRISTER N. JANSSON
The prominent Ungava Bay landform swarm (UBLS), covering an area of ,260000 km2 south of Ungava Bay, Canada, is defined by drumlins, crag-and-tails, horned crag-and-tails and flutes indicating convergent ice flow towards Ungava Bay. The UBLS has been difficult to interpret in terms of ice-sheet configuration, dynamics and age. Aerial photograph and satellite image interpretations of the Labrador-Ungava region reveal a previously unrecognized level of complexity within the UBLS consisting of several well-defined segments, most interpreted as representing discrete stream-flow events. Each of the segments is characterized by one or more of the criteria (convergent flow patterns at their heads, attenuated till lineations and abrupt lateral margins) previously suggested as diagnostic for formation by fast-flowing ice (ice streams). The UBLS reflects the most direct and probably fastest contact (in terms of sediment transport) between the Laurentide Ice Sheet interior and the ocean. It is therefore a prime candidate for abrupt changes in glacial-age northwest Atlantic seafloor sedimentation. [source]