Search results for "imagin."
showing 10 items of 7170 documents
The Role of Diffusion-Weighted Magnetic Resonance Imaging in Cholesteatoma Diagnosis and Follow-up: Study With the Diffusion PROPELLER Technique
2012
Abstract Introduction and objectives The diagnosis of cholesteatoma is based on clinical evaluation and computed tomography. New non-echo-planar diffusion-weighted magnetic resonance imaging (MRI) techniques, without intravenous contrast, are capable of differentiating cholesteatoma from inflammatory tissue, cholesterol granuloma and granulation tissues. The technique is very helpful in differential diagnosis of cholesteatoma, mainly after canal wall-up tympanoplasty surgery, to avoid routine second-look surgery in these patients. Congenital cholesteatoma and difficult cases can be detected and correctly diagnosed as well. The aim of this study was to evaluate sensitivity, specificity, posi…
Accuracy of magnetic resonance enterography in the preoperative assessment of patients with Crohn's disease of the small bowel
2016
Aim to assess the accuracy of magnetic resonance-enterography in predicting the extension, location and characteristics of the small bowel segments affected by Crohn's disease. Method This is a prospective study including a consecutive series of 38 patients with small bowel Crohn's disease who underwent surgery at a specialized colorectal unit of a tertiary hospital. Preoperative magnetic resonance enterography was performed in all patients, following a homogeneous protocol, within the three months prior to surgery. A thorough exploration of the small bowel was performed during the surgical procedure, using calibration spheres, according to the discretion of the surgeon. The accuracy of mag…
Developmental dyslexia: re-evaluation of the corpus callosum in male adults.
2000
Using a new method based upon the measurement of four angles, we analyzed the corpus callosum of 23 adult male dyslexics and 25 age-matched controls on MRI sagittal scans. Two out of the four angles measured showed significant differences between the groups that are consistent with previous findings concerning the size of the corpus callosum in dyslexics. In particular, posterior regions are concerned, displaying a lowered corpus callosum in dyslexics. These findings are discussed in relation to cortical parietal asymmetries and possible hormonal events, referring to the testosterone hypothesis, that could occur in utero or in the perinatal period in the dyslexic population.
Treatment of relapsing-remitting multiple sclerosis after 24 doses of natalizumab: evidence from an Italian spontaneous, prospective, and observation…
2014
Importance The evaluation of therapeutic choices is needed after 24 doses of natalizumab in patients with multiple sclerosis (MS). Objective To evaluate the effect of therapeutic choices on the mean annualized relapse rate and on magnetic resonance imaging MS activity after 24 doses of natalizumab in patients with relapsing-remitting MS. Design, Setting, and Participants The TY-STOP study, which recruited participants between October 22, 2010, and October 22, 2012, at 8 Italian MS centers (secondary care outpatient clinics) among 124 adult patients who demonstrated no clinical or magnetic resonance imaging MS activity after 24 doses of natalizumab. Interventions Natalizumab, no treatment, i…
Influence of age and sex on aortic distensibility assessed by MRI in healthy subjects
2010
International audience; Abstract: Magnetic resonance imaging (MRI) is particularly well adapted to the evaluation of aortic distensibility. The calculation of this parameter, based on the change in vessel cross-sectional area per unit change in blood pressure, requires precise delineation of the aortic wall on a series of cine-MR images. Firstly, the study consisted in validating a new automatic method to assess aortic elasticity. Secondly, aortic distensibility was studied for the ascending and descending thoracic aortas in 26 healthy subjects. Two homogeneous groups were available to evaluate the influence of sex and age (with an age limit value of 35 years). The automatic postprocessing …
Decline in motor prediction in elderly subjects: right versus left arm differences in mentally simulated motor actions.
2008
This study investigates the effects of age upon the temporal features of executed and imagined movements performed with the dominant (D; right) and nondominant (ND; left) arms. Thirty right-handed subjects were divided into two groups: (i) the young group (n=15; mean age: 22.5+/-2.5 years) and (ii) the elderly group (n=15; mean age: 70.2+/-2.2 years). The motor task, involving arm pointing movements among four pairs of targets (.5cm, 1cm, 1.5cm and 2cm), imposed strong spatiotemporal constraints. During overt performance, young and elderly subjects modulated movement duration according to the size of targets, despite the fact that movement speed decreased with age as well as in the left arm…
Mentally represented motor actions in normal aging: III. Electromyographic features of imagined arm movements.
2009
Abstract Motor imagery is a cognitive process during which subjects mentally simulate movements without actually performing them. Here, we investigated the temporal and electromyographic (EMG) features of imagined arm movements in healthy elderly adults. Twelve young (mean age: 24.0 ± 1.3 years) and 12 elderly (mean age: 67.0 ± 4.5 years) participants executed and mentally simulated, with their right and left arms and as fast and as accurately as possible, arm pointing movements between three targets located in the frontal plane. We used the mental chronometry paradigm as an indicator of the accuracy of the motor imagery process (i.e. isochrony between executed and imagined movements) and t…
Broad disruption of brain white matter microstructure and relationship with neuropsychological performance in male patients with severe alcohol depen…
2012
Aims In the last years, refined magnetic resonance diffusion tensor imaging (DTI) methods have become available to study microstructural alterations in the human brain. We investigated to what extent white matter tissue abnormalities are present in male patients after chronic, excessive alcohol consumption and if these alterations are correlated with measures of alcohol consumption and neuropsychological performance. Methods Twenty-four detoxified adult male patients with severe alcohol dependence and 23 healthy male control subjects were included in the study. Neuropsychological tests were assessed for executive function, attention, memory and visuospatial function. DTI was acquired and pr…
Prediction of rapid versus prolonged healing of infective endocarditis by monitoring vegetation size.
1991
The diagnostic value of transesophageal echocardiography in monitoring the clinical course has been evaluated in 83 patients with echocardiographic evidence of infective endocarditis. A total of 103 vegetations attached to the aortic or mitral valves were detected by use of the transesophageal approach. The patients were monitored for a mean of 74 weeks and underwent a minimum of two consecutive transesophageal echocardiographic examinations. Group A included patients with increasing or remaining constant size of vegetation (8.2 +/- 1.5 to 11.2 mm, p less than 0.05) during 4 to 8 weeks of antimicrobial therapy, whereas group B was formed by patients with decreasing vegetation size (8.3 +/- …
Aortic dissection detected by transoesophageal echocardiography
1986
The diagnostic value of transoesophageal echocardiography was evaluated in 24 patients with aortic dissection and compared to transthoracic two-dimensional echocardiography, computer tomography, aortography, surgery and autopsy. Using transoesophageal echocardiography we found in 5 patients a type I dissection, in 5 patients a type II and in 14 patients a type III dissection. Transthoracic two-dimensional echocardiography was positive in 3/5 type I, 2/5 in type II and 2/14 in type III dissections. Computer tomography was unable to demonstrate an intimal flap in 1/2 patients with type I, 2/3 type II and 1/11 type III dissections. Aortography was negative in 1/4 type I, 3/5 type II and 3/12 p…