Search Results
Results 301 - 350 of 1211
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Prescot Andrew P - - 2012
(1) H MRS investigations have reported altered glutamatergic neurotransmission in a variety of psychiatric disorders. The unraveling of glutamate from glutamine resonances is crucial for the interpretation of these observations, although this remains a challenge at clinical static magnetic field strengths. Glutamate resolution can be improved through an approach known ...
Wassilew Georgi I - - 2012
Diagnosis of acetabular retroversion is essential in femoroacetabular impingement (FAI), but its assessment from radiographs is complicated by pelvic tilt and the two-dimensional nature of plain films. We performed a study to validate the diagnostic accuracy of the cross-over sign (COS) and the posterior wall sign (PWS) in identifying acetabular ...
Votino C - - 2012
Objective: To examine whether high-field magnetic resonance (MR) imaging allows accurate estimation of various fetal organ weight in fetuses below 20 weeks of gestation. Methods: Twenty-three fetuses at 9-20 weeks and 207 various fetal organs were evaluated on high-field MR imaging at 9.4T prior to conventional autopsy. Fetal organ density ...
Pan Dipanjan - - 2012
We report a novel molecular imaging agent based on ytterbium designed for use with spectral "multicolor" computed tomography (CT). Spectral CT or multicolored CT provides all of the benefits of traditional CT, such as rapid tomographic X-ray imaging, but in addition, it simultaneously discriminates metal-rich contrast agents based on the ...
Shikhaliev Polad M - - 2012
Photon counting spectral computed tomography (PCSCT) provides material selective CT imaging at a single CT scan and fixed tube voltage. The PCSCT data are acquired in several energy ranges (bins) arranged over the x-ray spectrum. The quasi-monoenergetic CT images are acquired in these energy bins and are used for material ...
Nowinski Wieslaw L - - 2012
Knowledge of the cranial nerves and their nuclei is critical in clinical practice, medical research and education. However to our best knowledge, a comprehensive source capturing full three-dimensional (3D) relationships of the cranial nerves along with surrounding neuroanatomy is not yet available. This work addresses the construction and validation of ...
Smith Toby O TO Faculty of Medicine and Health Sciences, University of East Anglia, Queen's Building, Norwich, UK. - - 2012
Magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) have gained increasing favour in the assessment of patients with suspected glenoid labral injuries. The purpose of this study was to determine the diagnostic accuracy of MRI or MRA in the detection of gleniod labral lesions. A systematic review was undertaken ...
Li Chunjie - - 2012
To assess the diagnostic efficacy of ultrasonography in detecting disc displacement of the temporomandibular joint. MEDLINE (using OVID, 1950 to April 2011), EMBASE (1980 to April 2011), and the Chinese Biomedical Literature Database (1978 to April 2011) were searched electronically. In addition, relevant journals and reference lists of the included ...
Boutelier T - - 2012
A delay-insensitive probabilistic method for estimating hemodynamic parameters, delays, theoretical residue functions, and concentration time curves by computed tomography (CT) and magnetic resonance (MR) perfusion weighted imaging is presented. Only a mild stationarity hypothesis is made beyond the standard perfusion model. New microvascular parameters with simple hemodynamic interpretation are naturally ...
Guyomarc'h Pierre - - 2012
  Accuracy of forensic facial approximation and superimposition techniques relies on the knowledge of anatomical correlations between soft and hard tissues. Recent studies by Stephan and collaborators (6,8,10) reviewed traditional guidelines leading to a wrong placement of the eyeball in the orbit. As those statements are based on a small ...
Koh Jaehan - - 2012
PURPOSE: Disc herniation in the lumbar spine is a common condition, so an automated method for diagnosis could be helpful in clinical applications. A computer-aided framework for disk herniation diagnosis was developed for use in magnetic resonance imaging (MRI). MATERIALS AND METHOD: A computer-aided diagnosis framework for lumbar spine with ...
Naito Takehiro - - 2012
BACKGROUND: Hemodynamics in intracranial aneurysms is thought to play an important role in their growth and rupture. Usual computed fluid dynamics (CFD) based on three-dimensional (3D) computed tomographic (CT) angiography requires a time-consuming process for analysis. Magnetic resonance fluid dynamics (MRFD) based on MR images is a new tool for ...
Toya Ryo - - 2012
As there is continuing controversy over the role of F-18-fluorodeoxyglucose (FDG)-positron emission tomography (PET)⁄CT-fused imaging in radiation therapy (RT) planning, we performed a phantom study to assess the feasibility of FDG-PET/CT-based gross tumor volume (GTV) contouring. The phantom set, consisting of an elliptical bowl and 6 spheres measuring from 10-37 ...
Kaza Ravi K - - 2012
Several promising clinical applications for dual-energy computed tomography (CT) in genitourinary imaging have been reported. Dual-energy CT not only provides excellent morphologic detail but also can supply material-specific and quantitative information that may be particularly useful in genitourinary imaging. Dual-energy CT has unique capabilities for characterizing renal lesions by quantifying ...
Fritz Jan - - 2012
The purpose of this study was to prospectively evaluate the accuracy of an augmented reality image overlay system in MRI-guided spinal injection procedures. An augmented reality prototype was used in conjunction with a 1.5-T MRI system. A human lumbar spine phantom was used in which 62 targets were punctured to ...
Teeter Matthew G - - 2012
A significant amount of research has been undertaken to evaluate the function of implanted joint replacement components. Many of these studies require the acquisition of an accurate three-dimensional geometric model of the various implant components, using methods such as micro-computed tomography or laser scanning. The purpose of this study was ...
Ravesh M Salehi - - 2012
Tissue microcirculation can be quantified by a deconvolution analysis of concentration-time curves measured by dynamic contrast-enhanced magnetic resonance imaging. However, deconvolution is an ill-posed problem, which requires regularization of the solutions. In this work, four algebraic deconvolution/regularization methods were evaluated: truncated singular value decomposition and generalized Tikhonov regularization (GTR) in ...
Ju Bing-Feng - - 2012
The scanning speed of the two-dimensional stage dominates the efficiency of mechanical scanning measurement systems. This paper focused on a detailed scanning time analysis of conventional raster and spiral scan modes and then proposed two fast alternative scanning modes. Performed on a self-developed scanning acoustic microscope (SAM), the measured images ...
Chalian Hamid - - 2012
Purpose: To evaluate the reproducibility of liver tumor attenuation measurement performed by using the routinely used manual region-of-interest (ROI) method and that of measurement performed by using a semiautomated volumetric approach at computed tomography (CT). Materials and Methods: This HIPAA-compliant retrospective study had institutional review board approval. The requirement for ...
Gray William - - 2012
This article presents a novel, tightly integrated pipeline for estimating a connectome. The pipeline utilizes magnetic resonance (MR) imaging (MRI) data to produce a high-level estimate of the structural connectivity in the human brain. The MR connectome automated pipeline (MRCAP) is efficient, and its modular construction allows researchers to modify ...
Barghan S - - 2012
Radiographic examination is essential for the diagnosis and management of temporomandibular joint (TMJ) disorders. The goals of TMJ radiography are to evaluate cortical and trabecular architecture of the bony structures and confirm their integrity, to assess the extent and monitor progression of osseous changes, and to evaluate the response to ...
Murphy Keelin - - 2012
Purpose: To analyze pulmonary function using a fully automatic technique which processes pairs of thoracic CT scans acquired at breath-hold inspiration and expiration, respectively. The following research objectives are identified to: (a) describe and systematically analyze the processing pipeline and its results; (b) verify that the quantitative, regional ventilation measurements ...
Demehri Shadpour - - 2012
The purpose of this study was to test the hypothesis that the maximum axial area of ureteral stones is a more accurate predictor of spontaneous passage than the maximum axial diameter. This study retrospectively reviewed 211 consecutive emergency department patients (mean age, 48.8 years; age range, 18-88 years) with acute ...
Geethanath Sairam - - 2012
To retrospectively evaluate the fidelity of magnetic resonance (MR) spectroscopic imaging data preservation at a range of accelerations by using compressed sensing. The protocols were approved by the institutional review board of the university, and written informed consent to acquire and analyze MR spectroscopic imaging data was obtained from the ...
McArthur Benjamin - - 2012
Although cross-table lateral radiographs are commonly used to measure acetabular component version after THA, recent studies suggest that CT-based measurement is more accurate. This has been attributed to variations in pelvic tilt, pelvic rotation, and component inclination. Furthermore, it has been suggested, based on limited data, that even with ideal ...
Asferg Camilla - - 2012
BACKGROUND: Multi-slice computed tomography (MSCT) allows non-invasive assessment of the coronary arteries and simultaneously can provide measurement of left ventricular ejection fraction (LVEF). The accuracy of newer MSCT generations (64-slice or more) for assessment of LVEF compared with magnetic resonance imaging (MRI) and two-dimensional transthoracic echocardiography (TTE) has not been ...
Doan Nhat Trung - - 2012
PURPOSE: To propose a new method that integrates both magnitude and phase information obtained from magnetic resonance (MR) T*(2) -weighted scans for cerebral cortex segmentation of the elderly. MATERIALS AND METHODS: This method makes use of K-means clustering on magnitude and phase images to compute an initial segmentation, which is ...
Treece G M - - 2012
There is growing evidence that focal thinning of cortical bone in the proximal femur may predispose a hip to fracture. Detecting such defects in clinical CT is challenging, since cortices may be significantly thinner than the imaging system's point spread function. We recently proposed a model-fitting technique to measure sub-millimetre ...
Grigis Antoine - - 2012
This paper presents a longitudinal change detection framework for detecting relevant modifications in diffusion MRI, with application to neuromyelitis optica (NMO) and multiple sclerosis (MS). The core problem is to identify image regions that are significantly different between two scans. The proposed method is based on multivariate statistical testing which ...
Jilaihawi Hasan - - 2012
In an effort to define the gold standard for annular sizing for transcatheter aortic valve replacement (TAVR), we sought to critically analyze and compare the predictive value of multiple measures of the aortic annulus for post-TAVR paravalvular (PV) regurgitation and then assess the impact of a novel cross-sectional computed tomographic ...
Akashi Toshiaki - - 2012
PURPOSE: We hypothesized that the pattern of branching of the lenticulostriate arteries (LSAs) is involved in the variation of the distribution of the infarction within the LSA region. Our purpose was to evaluate the visibility of LSAs in 3D time-of-flight (TOF) MR angiography (MRA) with a 3.0 T scanner and to ...
Elsheikh Tarik M - - 2012
Based on current literature and the best available research to date, the current FDA workload limits for automated image-assisted screening, including the ThinPrep Imaging System and the FocalPoint GS, of 100 slides/day (imaged only slides counted as 0.5) are extremely high and may be associated with significant reduction in sensitivity. ...
Mueller Gabi - - 2012
Rib cage mobility decreases in various health conditions, for example neuromuscular diseases. A decrease in rib cage mobility reduces respiratory function and therefore increases the risk of respiratory complications. To evaluate the effects of interventions aiming at increasing rib cage mobility, changes should be calculated from measurements before and after ...
Makino Takahiro - - 2012
The measurement of transverse pedicle width is still recommended for selecting a screw diameter despite being weakly correlated with the minimum pedicle diameter, except in the upper lumbar spine. The purpose of this study was to reveal the difference between the minimum pedicle diameter and conventional transverse or sagittal pedicle ...
Bringard Aurélien - - 2012
Although simultaneous measurements of pulmonary oxygen uptake ( [Formula: see text] ) and Phosphorus-31 magnetic resonance spectroscopy ((31)P MRS) is attractive to investigate muscular metabolism during exercise, the superconducting magnet requires the design of specific gas exchange analyser (GEA). Thus, this study aimed to assess the validity of a commercial ...
Seehaus Arne K AK Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany. - - 2013
Despite several previous attempts, histological validation of diffusion-weighted magnetic resonance imaging (DW-MRI)-based tractography as true axonal fiber pathways remains difficult. In the present study, we establish a method to compare histological and tractography data precisely enough for statements on the level of single tractography pathways. To this end, we used ...
Smit Ewoud J - - 2012
Purpose:To suggest a simple and robust technique used to reconstruct high-quality computed tomographic (CT) angiographic images from CT perfusion data and to compare it with currently used CT angiography techniques.Materials and Methods:Institutional review board approval was waived for this retrospective study, which included 25 consecutive patients who had had a ...
Matsuno Wendy C - - 2012
OBJECTIVES: Computed tomographic (CT) scans are an accepted radiographic mode to the diagnosis of appendicitis. Radiologists play a critical role in its diagnostic accuracy. The purpose of this study was to determine whether there is a difference in the diagnostic accuracy between pediatric and general radiologists interpreting pediatric abdominal/pelvic CT ...
Claerhoudt S - - 2012
Reasons for performing study: Distal border synovial invaginations of the distal sesamoid bone are radiographically assessed during the selection process of horses admitted as breeding stallions or in purchase examinations. Nowadays, many moderately or some deeply penetrating proximally enlarged synovial invaginations are considered as moderate or severe radiographic findings. Objective: ...
Mauz Natacha - - 2012
OBJECTIVES: To investigate whether using 3 Tesla (T) instead of 1.5T modifies the data obtained from first-pass perfusion in relation to the quantitative values of cerebral blood volume (CBV) and estimation of micro-vascular leakage (MVL). To describe the differences in data in the setting of neuro-oncology cases and propose explanations ...
Wu Yi - - 2012
The structures of superior mediastinum and their spatial relationships are complex and difficult to master. This study aimed to compare visualization of the superior mediastinum based on computed tomography (CT) images and on the thin sections of the Chinese visible human (CVH) data set to provide a sectional anatomical basis ...
Leonova M A - - 2012
Spin resonances can depolarize or spin flip a polarized beam. We studied 1st and higher order spin resonances with stored 2.1  GeV/c vertically polarized protons. The 1st order vertical (ν_{y}) resonance caused almost full spin flip, while some higher order ν_{y} resonances caused partial depolarization. The 1st order horizontal (ν_{x}) resonance ...
Linguraru Marius George - - 2012
The interpretation of medical images benefits from anatomical and physiological priors to optimize computer-aided diagnosis applications. Diagnosis also relies on the comprehensive analysis of multiple organs and quantitative measures of soft tissue. An automated method optimized for medical image data is presented for the simultaneous segmentation of four abdominal organs ...
Elnakib A - - 2012
Dyslexia severely impairs learning abilities; therefore, improved diagnostic methods are needed. Neuropathological studies have revealed an abnormal anatomy of the Corpus Callosum (CC) in dyslexic brains. We propose a new approach for the quantitative analysis of three-dimensional (3D) Magnetic Resonance Images (MRI) of the brain that ensures a more accurate ...
Nomura Yoshikazu - - 2012
OBJECTIVES: The objective of this study was to investigate the stability of voxel values from cone-beam CT (CBCT) using a flat panel detector in changing surrounding circumstances mimicking clinical situations. MATERIALS AND METHODS: Seven hydroxyapatite (HA) rods (0, 40, 80, 120, 160, 199, and 239 mg Ca/cm(3) ) were set in a ...
Fang Z-M - - 2012
Objective:To establish a new magnetic resonance imaging scoring system for diagnosing endolymphatic hydrops.Patients and methods:A total of 214 ears of 107 patients were categorised into five groups: no symptoms, Ménière's disease, sudden deafness, delayed endolymphatic hydrops and other ear disorders. Gadolinium distribution within the labyrinth was scored separately and quantitatively ...
Beister Marcel - - 2012
Iterative reconstruction (IR) methods have recently re-emerged in transmission x-ray computed tomography (CT). They were successfully used in the early years of CT, but given up when the amount of measured data increased because of the higher computational demands of IR compared to analytical methods. The availability of large computational ...
Li Z - - 2012
AIM: To assess the severity of pure aortic regurgitation by measuring regurgitation volumes (RV) and fractions (RF) with dual-source computed tomography (DSCT) as compared to magnetic resonance imaging (MRI) and echocardiography. MATERIALS AND METHODS: Thirty-eight patients (15 men, 23 women; mean age 46±11 years) with isolated aortic valve regurgitation underwent ...
Tonolini Massimo - - 2012
Multidetector computed tomography (MDCT) cystography currently represents the modality of choice to image the urinary bladder in traumatized patients. In this review we present our experience with MDCT cystography applications outside the trauma setting, particularly for diagnosing bladder fistulas and leaks. A detailed explanation is provided concerning exam preparation, acquisition ...
Martín Joaquín - - 2012
PURPOSE: To review the anatomical landmarks of the abdominal wall lumbar region and its normal appearance on multidetector computed tomography (MDCT) and to briefly describe the MDCT features of lumbar hernias. METHODS: We performed a retrospective search of the imaging report database from November 2007 to October 2011. We retrieved ...
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