Search results for " ULTRASOUND"
showing 10 items of 818 documents
Review of imaging network activities in developing rodent cerebral cortex in vivo
2016
The combination of voltage-sensitive dye imaging (VSDI) with multielectrode array (MEA) recordings in the rodent cerebral cortex in vivo allows the simultaneous analysis of large-scale network interactions and electrophysiological single-unit recordings. Using this approach, distinct patterns of spontaneous and sensory-evoked activity can be recorded in the primary somatosensory (S1) and motor cortex (M1) of newborn rats. Already at the day of birth, gamma oscillations and spindle bursts in the barrel cortex synchronize the activity of a local columnar ensemble, thereby generating an early topographic representation of the sensory periphery. During the first postnatal week, both cortical ac…
High-Intensity Focused Ultrasound- and Radiation Therapy-Induced Immuno-modulation: Comparison and Potential Opportunities
2017
In recent years, high-intensity focused ultrasound (HIFU) has emerged as a new and promising non-invasive and non-ionizing ablative technique for the treatment of localized solid tumors. Extensive pre-clinical and clinical studies have evidenced that, in addition to direct destruction of the primary tumor, HIFU-thermoablation may elicit long-term systemic host anti-tumor immunity. In particular, an important consequence of HIFU treatment includes the release of tumor-associated antigens (TAAs), the secretion of immuno-suppressing factors by cancer cells and the induction of cytotoxic T lymphocyte (CTL) activity. Radiation therapy (RT) is the main treatment modality used for many types of tu…
Early silent microstructural degeneration and atrophy of the thalamocortical network in multiple sclerosis
2016
Recent studies on patients with clinically isolated syndrome (CIS) and multiple sclerosis (MS) demonstrated thalamic atrophy. Here we addressed the following question: Is early thalamic atrophy in patients with CIS and relapsing-remitting MS (RRMS) mainly a direct consequence of white matter (WM) lesions-as frequently claimed-or is the atrophy stronger correlated to "silent" (nonlesional) microstructural thalamic alterations? One-hundred and ten patients with RRMS, 12 with CIS, and 30 healthy controls were admitted to 3 T magnetic resonance imaging. Fractional anisotropy (FA) was computed from diffusion tensor imaging (DTI) to assess thalamic and WM microstructure. The relative thalamic vol…
Complexity analysis of cortical surface detects changes in future Alzheimer's disease converters
2017
Alzheimer's disease (AD) is a neurological disorder that creates neurodegenerative changes at several structural and functional levels in human brain tissue. The fractal dimension (FD) is a quantitative parameter that characterizes the morphometric variability of the human brain. In this study, we investigate spherical harmonic-based FD (SHFD), thickness, and local gyrification index (LGI) to assess whether they identify cortical surface abnormalities toward the conversion to AD. We study 33 AD patients, 122 mild cognitive impairment (MCI) patients (50 MCI converters and 29 MCI nonconverters), and 32 healthy controls (HC). SHFD, thickness, and LGI methodology allowed us to perform not only …
Automatic detection and measurement of nuchal translucency.
2017
In this paper we propose a new methodology to support the physician both to identify automatically the nuchal region and to obtain a correct thickness measurement of the nuchal translucency. The thickness of the nuchal translucency is one of the main markers for screening of chromosomal defects such as trisomy 13, 18 and 21. Its measurement is performed during ultrasound scanning in the first trimester of pregnancy. The proposed methodology is mainly based on wavelet and multi resolution analysis. The performance of our method was analysed on 382 random frames, representing mid-sagittal sections, uniformly extracted from real clinical ultrasound videos of 12 patients. According to the groun…
Ultrasonographic Measurements of the Achilles Tendon in Elderly Athletes and Sedentary Men
1994
Ultrasonography was performed on the Achilles tendon of the dominant limb of 18 male elderly athletes and 11 sedentary men, aged 70 to 80 years. The tendons were examined with a real-time linear array scanner using a 7.5 MHz transducer. Both longitudinal and transverse images were taken. The mean width of the Achilles tendon was significantly larger in the athletes than in the control subjects. The tendon thickness and cross-sectional area did not differ significantly between the groups, but the figures may indicate a tendency for larger cross-sectional area in the athletes. The results suggest tendon hypertrophy following long-term training.
The “central dot sign” in acute epiploic appendagitis
2018
Epiploic appendagitis is the acute inflammation and infarction of epiploic appendages, commonly secondary to torsion. It is a great mimicker as its clinical manifestation may be similar to appendicitis, diverticulitis, or colitis. Focal abdominal pain, tenderness, and mild pyrexia are clinical features of the condition [1]. Epiploic appendages are pedunculated adipose structures which extend from the serosal surface of the colon, along the free taenia and taenia omentalis. They are abundant in the caecum and sigmoid colon and absent in the rectum
Ultrasonography (US) in the assessment of pediatric non traumatic gastrointestinal emergencies
2013
AbstractBackgroundNon traumatic gastrointestinal emergencies in the children and neonatal patient is a dilemma for the radiologist in the emergencies room and they presenting characteristics ultrasound features on the longitudinal and axial axis. The most frequent emergencies are : appendicitis, intussusceptions, hypertrophic pyloric stenosis, volvulus due to intestinal malrotation. The aim of this article is to familiarize the reader with the US features.MethodsA retrospective analysis of 200 ultrasound examinations performed in neonatal and children patients with fever, abdominal pain, leukocytosis, vomiting and diarrhea were evaluated.ResultsOf 200 exame 50 cases of intussusceptions, 100…
Accurate estimation of retinal vessel width using bagged decision trees and an extended multiresolution Hermite model.
2012
We present an algorithm estimating the width of retinal vessels in fundus camera images. The algorithm uses a novel parametric surface model of the cross-sectional intensities of vessels, and ensembles of bagged decision trees to estimate the local width from the parameters of the best-fit surface. We report comparative tests with REVIEW, currently the public database of reference for retinal width estimation, containing 16 images with 193 annotated vessel segments and 5066 profile points annotated manually by three independent experts. Comparative tests are reported also with our own set of 378 vessel widths selected sparsely in 38 images from the Tayside Scotland diabetic retinopathy scre…
Effects of ultrasound and temperature on copper electro reduction in Deep Eutectic Solvents (DES).
2014
Abstract This paper concerns a preliminary study for a new copper recovery process from ionic solvent. The aim of this work is to study the reduction of copper in Deep Eutectic Solvent (choline chloride–ethylene glycol) and to compare the influence of temperature and the ultrasound effects on kinetic parameters. Solutions were prepared by dissolution of chloride copper salt CuCl 2 (to obtain Copper in oxidation degree II) or CuCl (to obtain Copper in oxidation degree I) and by leaching metallic copper directly in DES. The spectrophotometry UV–visible analysis of the leached solution showed that the copper soluble form obtained is at oxidation degree I (Copper I). Both cyclic voltammetry and…