Search results for " INTERPRETATION"
showing 10 items of 555 documents
Solitary necrotic nodules of the liver: cross-sectional imaging findings and follow-up in nine patients.
2008
OBJECTIVE. The purpose of our study was to retrospectively evaluate the sonographic, CT, and MRI findings (number, diameter, lobar location, depth from the hepatic capsule, and appearance of lesions) in a series of nine patients with pathologically proven solitary necrotic nodules of the liver and the natural evolution at follow-up in four of the nine patients.CONCLUSION. Solitary necrotic nodules are usually small, solitary lesions, mainly located under the liver capsule of the right lobe. They are hypoechoic on sonography, hypoattenuating on CT, have low signal intensity on both T1- and T2-weighted MRI with lack of enhancement after IV contrast administration, and at follow-up have a tend…
Noise estimation from averaged diffusion weighted images: Can unbiased quantitative decay parameters assist cancer evaluation?
2013
Purpose Multiexponential decay parameters are estimated from diffusion-weighted-imaging that generally have inherently low signal-to-noise ratio and non-normal noise distributions, especially at high b-values. Conventional nonlinear regression algorithms assume normally distributed noise, introducing bias into the calculated decay parameters and potentially affecting their ability to classify tumors. This study aims to accurately estimate noise of averaged diffusion-weighted-imaging, to correct the noise induced bias, and to assess the effect upon cancer classification. Methods A new adaptation of the median-absolute-deviation technique in the wavelet-domain, using a closed form approximati…
MAGIC-5: an Italian mammographic database of digitised images for research
2008
The implementation of a database of digitised mammograms is discussed. The digitised images were collected beginning in 1999 by a community of physicists in collaboration with radiologists in several Italian hospitals as a first step in developing and implementing a computer-aided detection (CAD) system. All 3,369 mammograms were collected from 967 patients and classified according to lesion type and morphology, breast tissue and pathology type. A dedicated graphical user interface was developed to visualise and process mammograms to support the medical diagnosis directly on a high-resolution screen. The database has been the starting point for developing other medical imaging applications,…
Focal confluent fibrosis in cirrhotic liver: natural history studied with serial CT.
2009
The objective of this study was to assess the long-term natural history of focal confluent fibrosis in cirrhotic liver with CT.Two radiologists retrospectively reviewed in consensus 118 liver CT examinations in 26 patients (19 men, seven women; age range, 32-68 years; mean age, 50 years) performed over approximately 6 years. Helical CT scans were obtained before and 30-35 and 65-70 seconds after injection of 125-150 mL of contrast medium at a rate of 4-5 mL/s. Proof of cirrhosis was based on liver transplantation (n = 6), biopsy (n = 9), or imaging findings (n = 11). The number, location, and attenuation of fibrotic lesions and presence of trapped vessels were evaluated. Variation of hepati…
Diagnostic value of MR-based texture analysis for the assessment of hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD)
2019
PurposeTo investigate the performance of MR-based texture analysis (TA) for the assessment of hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD).MethodsFifty-four adult patients (33 females, 21 males, mean age 49.813.5years) with biopsy-proven NAFLD were enrolled and underwent MR imaging on a 1.5T system. TA parameters were extracted on axial noncontrast 3D-GRE T1W images (slice thickness=4.6mm) using a commercially available research software (TexRAD). Receiver operating curves (ROC), areas under the ROC (AUROC) and 95% confidence intervals (CI) were calculated to assess the accuracy of each TA parameter for the diagnosis of significant (F2) and advanced fibrosis (F…
A semi-automatic approach for epicardial adipose tissue segmentation and quantification on cardiac CT scans
2019
Abstract Many studies have shown that epicardial fat is associated with a higher risk of heart diseases. Accurate epicardial adipose tissue quantification is still an open research issue. Considering that manual approaches are generally user-dependent and time-consuming, computer-assisted tools can considerably improve the result repeatability as well as reduce the time required for performing an accurate segmentation. Unfortunately, fully automatic strategies might not always identify the Region of Interest (ROI) correctly. Moreover, they could require user interaction for handling unexpected events. This paper proposes a semi-automatic method for Epicardial Fat Volume (EFV) segmentation a…
Reliability and validity of the Digigraph 100 in orthodontic diagnosis.
2001
Cephalometric analyses of lateral cephalograms allow important statements to be made on diagnosis and treatment planning. Such radiographs should, however, be taken with a considerable reduction in radiation exposure. With the Digigraph 100 (Dolphin Imaging Systems Inc., USA) a cephalometric technique based on distance measurements of emitted sonic signals is now available. This study was aimed at determining the degree to which this procedure can cope with the requirements of reliability and validity in the field of orthodontics. For this purpose 50 volunteers were examined by conventional cephalometry with manual tracing of lateral cephalograms as well as by sonic cephalometry, with Jarab…
Linking planning performance and gray matter density in mid-dorsolateral prefrontal cortex: Moderating effects of age and sex
2012
Abstract Planning of behavior relies on the integrity of the mid-dorsolateral prefrontal cortex (mid-dlPFC). Yet, only indirect evidence exists on the association of protracted maturation of dlPFC and continuing gains in planning performance post adolescence. Here, gray matter density of mid-dlPFC in young, healthy adults (18–32 years) was regressed onto performance on the Tower of London planning task while accounting for moderating effects of age and sex on this interrelation. Multiple regression analysis revealed an association of planning performance and mid-dlPFC gray matter density that was especially strong in late adolescence and early twenties. As expected, for males better plannin…
Eyes open and eyes closed as rest conditions: impact on brain activation patterns
2003
The patterns of associated brain activations during eyes-open and eyes-closed states in complete darkness considerably differ in fMRI. An "interoceptive" state with the eyes closed is characterized by visual cortex activation, while an "exteroceptive" state with the eyes open is characterized by ocular motor system activity. The impact of the chosen rest condition (eyes open or eyes closed in complete darkness) on the pattern of brain activations during visual stimulation was evaluated in 14 healthy volunteers. During fixation or dim light room illumination, the activation of the visual cortex was larger with the eyes-open rest condition than with the eyes-closed rest condition; however, ac…
Neural substrates of the interaction of emotional stimulus processing and motor inhibitory control: an emotional linguistic go/no-go fMRI study.
2007
Neural substrates of behavioral inhibitory control have been probed in a variety of animal model, physiologic, behavioral, and imaging studies, many emphasizing the role of prefrontal circuits. Likewise, the neurocircuitry of emotion has been investigated from a variety of perspectives. Recently, neural mechanisms mediating the interaction of emotion and behavioral regulation have become the focus of intense study. To further define neurocircuitry specifically underlying the interaction between emotional processing and response inhibition, we developed an emotional linguistic go/no-go fMRI paradigm with a factorial block design which joins explicit inhibitory task demand (i.e., go or no-go)…