Search results for "Radiological and Ultrasound Technology"
showing 10 items of 423 documents
Post‐COVID ‐19 Liver Injury: Comprehensive Imaging With Multiparametric Ultrasound
2021
OBJECTIVES: This study aimed to define patterns of liver injury after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using multiparametric ultrasound (mpUS) in a variable patient population with differing severities of COVID-19. METHODS: Ninety patients were enrolled into the study: 56 had SARS-CoV-2 3-9 months prior to enrolment; 34 served as a clinically healthy control group. All patients underwent an mpUS evaluation of the liver (elastography, dispersion and attenuation imaging). Seventy-six patients had abdominal magnetic resonance (MR) and noncontrast enhanced thoracic computed tomography (CT) scans performed at the same day. All patients were screened for bioc…
What we learn about bipolar disorder from large-scale neuroimaging
2020
Abstract MRI‐derived brain measures offer a link between genes, the environment and behavior and have been widely studied in bipolar disorder (BD). However, many neuroimaging studies of BD have been underpowered, leading to varied results and uncertainty regarding effects. The Enhancing Neuro Imaging Genetics through Meta‐Analysis (ENIGMA) Bipolar Disorder Working Group was formed in 2012 to empower discoveries, generate consensus findings and inform future hypothesis‐driven studies of BD. Through this effort, over 150 researchers from 20 countries and 55 institutions pool data and resources to produce the largest neuroimaging studies of BD ever conducted. The ENIGMA Bipolar Disorder Workin…
Correlation of Tibial Low-Frequency Ultrasound Velocity with Femoral Radiographic Measurements and BMD in Elderly Women
2009
The ultrasonic axial transmission technique has been proposed as a method for cortical bone characterization. Using a low enough center frequency, Lamb modes can be excited in long bones. Lamb waves propagate throughout the cortical bone layer, which makes them appealing for characterizing bone material and geometrical properties. In the present study, a prototype low-frequency quantitative ultrasonic axial transmission device was used on elderly women (n = 132) to investigate the relationships between upper femur geometry and bone mineral density (BMD) and tibial speed of sound. Ultrasonic velocities (V) were recorded using a two-directional measurement set-up on the midtibia and compared …
Ultrasound-guided musculoskeletal interventional procedures around the elbow, hand and wrist excluding carpal tunnel procedures.
2021
Ultrasound is a fast, reliable and radiation-free method for the assessment of a wide range of pathological conditions, as well as for the guidance of percutaneous interventional procedures around the elbow, hand and wrist. Intraarticular and periarticular interventional procedures can be easily performed under continuous ultrasound monitoring to ensure correct needle positioning and medication delivery to a specific target. The most common ultrasound-guided procedures performed around the elbow, wrist, and hand are described in this review, excluding carpal tunnel procedures. Specifically, elbow steroid injections are performed in patients with inflammatory disorders, while hyaluronic acid…
MRI findings and evoked potentials in patients with myotonic dystrophy versus facioscapulohumeral dystrophy
1997
Evoked potentials recordings have been applied to many neurological disorders, localizing the lesions in the central nervous system (CNS) pathways. Facioscapulohumeral muscular dystrophy (FSHD) is a slowly progressive degenerative disease involving the muscles of the face and shoulders. On the contrary, myotonic distrophy (MD), the most frequent and severe myotonic disease, is caracterized by myotonia (delay of relaxation after voluntary contraction), muscular atrophy and dystrophic changes in non-muscular tissues. In the present investigation, patients with clinically and electromyographically verified FSHD and MD were examined using somatosensory evoked potentials (SEP) and brainstem aud…
The arterial blood supply of the temporomandibular joint: an anatomical study and clinical implications
2013
Purpose: The aim of this study was to analyze three-dimensional images of the arterial supply to the temporomandibular joint. Materials and Methods: Ten patients (five men and five women, mean age 36 years) without signs or symptoms of temporomandibular disorders, who underwent contrast-enhanced computed tomographic (CT) scanning with intravenous contrast, were studied. The direct volume rendering technique of CT images was used, and a data set of images to visualize the vasculature of the human temporomandibular joint in three dimensions was created. After elaboration of the data through post-processing, the arterial supply of the temporomandibular joint was studied. Results: The analysis …
A study of Type B uncertainties associated with the photoelectric effect in low-energy Monte Carlo simulations
2021
The goal of this manuscript is to estimate Type B uncertainties in absorbed-dose calculations arising from the different implementations in current state-of-the-art Monte Carlo codes of low-energy photon cross-sections (<200 keV). Monte Carlo simulations are carried out using three codes widely used in the low-energy domain: PENELOPE-2018, EGSnrc, and MCNP. Mass energy-absorption coefficients for water, air, graphite, and their respective ratios; absorbed dose; and photon-fluence spectra are considered. Benchmark simulations using similar cross-sections have been performed. The differences observed between these quantities when different cross-sections are considered are taken to be a go…
Ultrasound bioeffects in rats: quantification of cellular damage in the fetal liver after pulsed Doppler imaging
2011
Objective To determine whether pulsed Doppler examination of the ductus venosus in rat fetuses could damage exposed tissue. Methods On gestational day 18, the livers of a mean of approximately five fetuses per mother (n = 5.14, SD = 1.6), in a cohort of 35 pregnant female rats, were exposed individually to pulsed Doppler and these were considered the 'exposed group'. The remaining fetuses in each pregnant rat (n = 5.16, SD = 2.1) formed the 'control group'. We tested for 600, 300, 60, 20, 15, 10 and 3 s of exposure of the fetal ductus venosus and the damage was evaluated measuring a cell death index of apoptotic activity at 7 h post-exposure (n = 16). In addition, subgroups of mothers were …
Shoulder ultrasound: current concepts and future perspectives
2021
Ultrasonography is an established and effective imaging technique that can be used to evaluate articular and periarticular structures around the shoulder. It has been shown to be useful in a wide range of rotator cuff diseases (e.g. tendon tears, rotator cuff calcific tendinopathy and bursitis) as well as non-rotator cuff abnormalities (instability, synovial joint diseases and nerve entrapment syndrome). A scanning protocol is highly recommended to reduce the rate of operators’ errors by following a standardized scheme including a list of main structures. Shoulder ultrasound has several advantages: it is a relatively cheap and widely available technique, free from ionizing radiation, that c…
THE RELATIONSHIP BETWEEN WOMEN´S ARTISTIC GYMNASTICS TECHNICAL SKILL, PHYSICAL PERFORMANCE TEST RESULTS AND SUCCESS IN COMPETITIONS IN FINLAND
2019
The aim of this study was to find out the potential of the Minoritest to identify the most likely talented gymnasts to join the national team pre-training group in Finland. The study examined the relationships between gymnasts´ (N=215, age 10–13) Minoritest results (2006–2010) and success in competitions after the Minoritests until the end of 2016. The competition results were also compared between the gymnasts who had participated in the test and a random number (N=180) of gymnasts who had not. According to this study, the majority (92%) of the best gymnasts in competitions had participated in the Minoritest. 39% of the best in competitions were among the top 10 in the Minoritest. The test…