Search results for "sonography"
showing 10 items of 978 documents
Viscoelastic properties of the Achilles tendon in vivo
2013
It has been postulated that human tendons are viscoelastic and their mechanical properties time-dependent. Although Achilles tendon (AT) mechanics are widely reported, there is no consensus about AT viscoelastic properties such as loading rate dependency or hysteresis, in vivo. AT force-elongation characteristics were determined from 14 subjects in an ankle dynamometer at different loading rates using motion capture assisted ultrasonography. AT stiffness and elongation were determined between 10 – 80% of maximum voluntary contraction (MVC) force at fast and slow loading rates. As subjects were unable to consistently match the target unloading rate in the slow condition, AT hysteresis was on…
Relation between bone quality values from ultrasound transmission velocity and implant stability parameters--an ex vivo study.
2011
Aim The objective of this study was to determine the relationship between bone qualities measured by ultrasound transmission velocity (UTV) and primary implant stability parameters measured by radiofrequency analysis (RFA) and push-out test (POT) in an ex-vivo model. Materials and methods Three blocks of fresh porcine bone samples were obtained from different anatomic regions, correlating to cortical, mixed and cancellous bone. Mechanical bone qualities of these samples were measured using UTV (expressed in m/s) prior to implantation. Three similar implants (4.1 × 11 mm, AstraTech OS) were inserted into each of the procured bone blocks. The evaluation of implant-bone interface stability was…
Behaviour of vastus lateralis muscle-tendon during high intensity SSC exercises in vivo
2003
Aims: The interaction between fascicle and tendinous tissue of human vastus lateralis muscle was investigated during varying intensity stretch–shortening cycle (SSC) jumps performed on a sledge apparatus. Methods: Eight subjects performed single leg squat (SJ) and drop jumps (DJ) from a constant dropping height but to different rebound heights. The fascicle length of the vastus lateralis muscle (VL) was determined from real-time ultrasonography during the movement. Tendon length changes were calculated by subtracting the horizontal part of the fascicle length from the muscle–tendon unit (MTU) length. Simultaneously, kinematic, kinetic and electromyographic data were recorded from leg musc…
Contrast-Enhanced Ultrasound Qualitative and Quantitative Characteristics of Parathyroid Gland Lesions
2021
Background and Objectives: preoperative differentiation of enlarged parathyroid glands may be challenging in conventional B-mode ultrasound. The aim of our study was to analyse qualitative and quantitative characteristics of parathyroid gland lesions, using multiparametric ultrasound protocol—B-mode, Colour Doppler (CD), and contrast-enhanced ultrasound (CEUS)—and to evaluate correlation with morphology in patients with hyperparathyroidism (HPT). Materials and Methods: consecutive 75 patients with 88 parathyroid lesions and biochemically confirmed HPT prior to parathyroidectomy were enrolled in the prospective study. B-mode ultrasound, CD, and CEUS were performed with the subsequent qualita…
Does Function Determine the Structure? Changes in Flexor Hallucis Longus Muscle and the Associated Performance Related to Dance Modality: A Cross-Sec…
2020
Background and Objectives: Flexor hallucis longus pathology is one of the most common conditions of the ankle and foot in dancers, due to the high demand of dance movements performed in an extreme plantar flexion and dorsiflexion range of motion. The objectives of this study were to determine the bilateral differences between the thickness and cross-sectional area of the flexor hallucis longus muscle in dancers, to establish possible differences between dance modalities, and to analyze whether there is a correlation between ultrasonographic parameters or performance variables and the dance modality. Material and Methods: A sample of 50 (29 classical and 21 contemporary) full-time pre-profes…
Focal Pancreatic Lesions: Role of Contrast-Enhanced Ultrasonography.
2021
The introduction of contrast-enhanced ultrasonography (CEUS) has led to a significant improvement in the diagnostic accuracy of ultrasound in the characterization of a pancreatic mass. CEUS, by using a blood pool contrast agent, can provide dynamic information concerning macro- and micro-circulation of focal lesions and of normal parenchyma, without the use of ionizing radiation. On the basis of personal experience and literature data, the purpose of this article is to describe and discuss CEUS imaging findings of the main solid and cystic pancreatic lesions with varying prevalence.
Immunological diagnosis of human hydatid cyst relapse: utility of the enzyme-linked immunoelectrotransfer blot and discriminant analysis.
2000
ABSTRACT A discriminant technique was applied to the different serological patterns obtained by enzyme-linked immunoelectrotransfer blotting (EITB) and by conventional immunological tests, in order to differentiate the residual antibody patterns present in healed hydatidosis from the ones present in patients with active hydatidosis. For this purpose, specific antibodies against Echinococcus granulosus were detected by indirect hemagglutination, agglutination of latex particles, basophil degranulation, and EITB for 23 patients with active hydatidosis and 45 patients with surgically cured hydatidosis. Discriminant analysis of the different serological patterns obtained by EITB and conventiona…
Is it possible to predict late antepartum stillbirth by means of cerebroplacental ratio and maternal characteristics?
2019
Objective: To examine the potential value of fetal ultrasound and maternal characteristics in the prediction of antepartum stillbirth after 32 weeks’ gestation. Methods: This was a retrospective multicenter study in Spain. In 29 pregnancies, umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI), cerebroplacental ratio (CPR), estimated fetal weight (EFW), and maternal characteristics were recorded within 15 days prior to a stillbirth. The values of UA PI, MCA PI, and CPR were converted into multiples of the normal median (MoM) for gestational age and the EFW was expressed as percentile according to a Spanish reference range for gestational age. Data fr…
Intraosseous monitoring of drilling in lumbar vertebrae by ultrasound: An experimental feasibility study.
2016
The rationale for this project is to evaluate the efficiency of a novel sonographic method for measurements of interosseous distances. The method utilizes a propagating ultrasonic beam through aqueous milieu which is directed as a jet into a drilled tract. We used a plastic model of human L5 vertebra and ex vivo specimen of L5 porcine vertebra and generated 2 mm in diameter tracts in vertebral pedicles. The tracts were created in the "desired" central direction and in the "wrong" medial and lateral directions. The drilled tracts and the residual, up to opposite cortex, distances were measured sonographically and mechanically and compared statistically. We show that "true" mechanical measure…
Ultrasound protocol in odontogenic infections: a new proposal
2022
Point-of-care-ultrasound can be applied to preview a difficult airway, detect the presence of fluid collection, and soft-tissue edema, and guide the drainage location, although is rarely used. The purpose of this study is to validate a protocol for the assessment of these clinical features on patients with severe odontogenic infections. This was a single-group prospective cohort study (n=20) including patients with the diagnosis of deep-neck propagation of odontogenic infection. A transcervical linear high-frequency probe transducer (13-6 MHz) was used to scan the structures of the upper airway and the infectious collections. The drainage was guided by ultrasound and the patients were daily…