Search results for "RESONANCE"
showing 10 items of 6625 documents
Key issues in decomposing fMRI during naturalistic and continuous music experience with independent component analysis
2014
Background: Independent component analysis (ICA) has been often used to decompose fMRI data mostly for the resting-state, block and event-related designs due to its outstanding advantage. For fMRI data during free-listening experiences, only a few exploratory studies applied ICA.New method: For processing the fMRI data elicited by 512-s modern tango, a FFT based band-pass filter was used to further pre-process the fMRI data to remove sources of no interest and noise. Then, a fast model order selection method was applied to estimate the number of sources. Next, both individual ICA and group ICA were performed. Subsequently, ICA components whose temporal courses were significantly correlated …
Influence of myocardial fibrosis and blood oxygenation on heart T2* values in thalassemia patients
2009
Purpose To determine whether T2* measurements quantifying myocardial iron overload in thalassemia patients are influenced by myocardial fibrosis and blood oxygenation. Materials and Methods Multislice multiecho T2* was performed in 94 thalassemia patients in order to quantify myocardial iron overload. The left ventricle was automatically segmented into a 16-segment standardized heart model, and the T2* value on each segment as well as the global T2* were calculated. Delayed enhanced cardiovascular magnetic resonance (DE-CMR) images were obtained to detect myocardial fibrosis. The blood oxygenation was assessed by the noninvasive measurement of partial pressure of oxygen (pO2). Results Myoca…
Dynamic MR imaging of breast lesions: correlation with microvessel distribution pattern and histologic characteristics of prognosis.
2006
To evaluate the association of dynamic enhancement parameters of benign and malignant breast lesions at magnetic resonance (MR) imaging with microvessel distribution and histologic prognostic tumor characteristics.Regional review board approval and informed consent were obtained. Surgical resection specimens of breast lesions (32 benign, 86 malignant) in 118 patients (age range, 28-86 years; mean, 58 years) who had undergone dynamic T1-weighted MR imaging of both breasts were included in the study. Different MR enhancement parameters and microvessel density (MVD) distribution were determined. In malignant lesions, TNM stage, tumor grade, proliferative activity, and hormone receptor expressi…
Different neuronal contribution to N20 somatosensory evoked potential and to CO2 laser evoked potentials: an intracerebral recording study
2004
Abstract Objective : To investigate the possible contribution of the primary somatosensory area (SI) to pain sensation. Methods : Depth recordings of CO 2 laser evoked potentials (LEPs) and somatosensory evoked potentials (SEPs) were performed in an epileptic patient with a stereotactically implanted electrode (Talairach coordinates y =−23, z =40) that passed about 10 mm below the hand representation in her left SI area, as assessed by the source of the N20 SEP component. Results : The intracerebral electrode was able to record the N20 SEP component after non-painful electrical stimulation of her right median nerve. The N20 potential showed a phase reversal in the bipolar montage (at about …
Dyke-Davidoff-Masson syndrome: case report of fetal unilateral ventriculomegaly and hypoplastic left middle cerebral artery
2013
Prenatal ultrasonographic detection of unilateral cerebral ventriculomegaly arises suspicion of pathological condition related to cerebrospinal fluid flow obstruction or cerebral parenchimal pathology. Dyke-Davidoff-Masson syndrome is a rare condition characterized by cerebral hemiatrophy, calvarial thickening, skull and facial asymmetry, contralateral hemiparesis, cognitive impairment and seizures. Congenital and acquired types are recognized and have been described, mainly in late childhood, adolescence and adult ages. We describe a female infant with prenatal diagnosis of unilateral left ventriculomegaly in which early brain MRI and contrast enhanced-MRI angiography, showed cerebral left…
Exercise loading history and femoral neck strength in a sideways fall: A three-dimensional finite element modeling study
2016
Over 90% of hip fractures are caused by falls. Due to a fall-induced impact on the greater trochanter, the posterior part of the thin superolateral cortex of the femoral neck is known to experience the highest stress, making it a fracture-prone region. Cortical geometry of the proximal femur, in turn, reflects a mechanically appropriate form with respect to habitual exercise loading. In this finite element (FE) modeling study, we investigated whether specific exercise loading history is associated with femoral neck structural strength and estimated fall-induced stresses along the femoral neck. One hundred and eleven three-dimensional (3D) proximal femur FE models for a sideways falling situ…
Validation of tumour-free distance as novel prognostic marker in early-stage cervical cancer: a retrospective, single-centre, cohort study
2021
Background: The aim of the present study was to assess the prognostic value of tumour-free distance (TFD), defined as the minimum distance of uninvolved stroma between the tumour and peri-cervical stromal ring, in early-stage cervical cancer. Methods: Patients with pathologic FIGO 2009 stage IA1–IIA2 cervical cancer, treated by primary radical surgical treatment between 01/2000 and 11/2019, were retrospectively included. Adjuvant treatment was administered according to the presence of previously established pathologic risk factors. TFD was measured histologically on the hysterectomy specimen. Pre-operative TFD measured at MRI-scan from a cohort of patients was reviewed and compared with pat…
Neural correlates of antinociception in borderline personality disorder.
2006
Context A characteristic feature of borderline personality disorder (BPD) is self-injurious behavior in conjunction with stress-induced reduction of pain perception. Reduced pain sensitivity has been experimentally confirmed in patients with BPD, but the neural correlates of antinociceptive mechanisms in BPD are unknown. We predicted that heat stimuli in patients with BPD would activate brain areas concerned with cognitive and emotional evaluation of pain. Objective To assess the psychophysical properties and neural correlates of altered pain processing in patients with BPD. Design Case-control study. Setting A university hospital. Participants Twelve women with BPD and self-injurious behav…
Intratumoral Haemorrhage Causing an Unusual Clinical Presentation of a Vestibular Schwannoma
2012
We present a case of an elderly woman with no history of audiological disease with sudden onset of visual and hearing deficits associated with systemic clinical signs. On examination she had impairment of right CNs from V to X. CT and MR imaging demonstrated a cystic vestibular schwannoma with a rare intralesional fluid-fluid level correlated to a recent bleed. We include high quality MR images to show the acute impairment of the cranial nerves next to the tumour after acute bleeding. Our case report includes a voxel-based morphometry (VMB) analysis of the tumour that, as far as we know, has never been done before for such a tumour. VBM analysis was performed to calculate the hypothesized …
Ex vivo high resolution magic angle spinning metabolic profiles describe intratumoral histopathological tissue properties in adult human gliomas.
2010
In gliomas one can observe distinct histopathological tissue properties, such as viable tumor cells, necrotic tissue or regions where the tumor infiltrates normal brain. A first screening between the different intratumoral histopathological tissue properties would greatly assist in correctly diagnosing and prognosing gliomas. The potential of ex vivo high resolution magic angle spinning spectroscopy in characterizing these properties is analyzed and the biochemical differences between necrosis, high cellularity and border tumor regions in adult human gliomas are investigated. Statistical studies applied on sets of metabolite concentrations and metabolite ratios extracted from 52 high resolu…