Using shear wave elastography, we measure the changes in the wave speed with the stress produced by a striated muscle during isometric voluntary contraction. To isolate the behaviour of an individual ...muscle from complementary or antagonistic actions of adjacent muscles, we select the
muscle, whose sole function is to extend the little finger. To link the wave speed to the stiffness, we develop an acousto-elastic theory for shear waves in homogeneous, transversely isotropic, incompressible solids subject to an uniaxial stress. We then provide measurements of the apparent shear elastic modulus along, and transversely to, the fibre axis for six healthy human volunteers of different age and sex. The results display a great variety across the six subjects. We find that the slope of the apparent shear elastic modulus along the fibre direction changes inversely to the maximum voluntary contraction (MVC) produced by the volunteer. We propose an interpretation of our results by introducing the S (slow) or F (fast) nature of the fibres, which harden the muscle differently and accordingly, produce different MVCs. A natural follow-up on this study is to apply the method to patients with musculoskeletal disorders or neurodegenerative diseases.
Ultrasound is currently recommended as the first-line examination for abdominal symptoms in children. However, a pediatric radiologist is not always available on site, especially during on-call duty. ...This study was aimed at evaluating the reliability of an innovative 3-D virtual abdominal tele-ultrasonography in this context. A prospective study was conducted between December 2020 and May 2021 that recruited 103 children undergoing ultrasound for abdominal pain. Trauma cases were excluded. Four tridimensional acquisitions were performed with a Smart Sensor 3D device (Canon Medical Systems, Otawara, Japan). Each tele-ultrasonography was secondarily blindly reviewed by two radiologists (one senior and one resident) with Fusion software (Canon Medical Systems). Acceptance and quality of the acquisitions were evaluated on a Likert scale. Inter-rater reliability was quantified using Cohen's κ coefficient and intraclass correlation coefficient. The ultrasound examination was normal in 66 cases (64%), abnormal in 36 cases (35%) and inconclusive in 1 case (1%). The acquisitions were obtained without objections from the children, their parents or the operators in more than 95% of cases. The quality of the acquisitions was considered good to excellent in 84% and 70% of cases. The sensitivity of the senior radiologist and the resident was 86% and 84%, respectively; specificity was 95% and 92%, positive predictive value 92% and 86% and negative predictive value 92 and 91% when comparing the conclusions of the standard and the tele-ultrasound examinations. Cohen's κ coefficients of the diagnosis obtained with the standard and the tele-ultrasound examinations were 0.82 and 0.71, respectively. The inter-rater Cohen's κ coefficient was 0.84. The intraclass correlation coefficient between the standard abdominal examination and the 3-D tele-ultrasound reformatted images for the following quantitative variables on pathological cases was 0.99 (confidence interval: 0.98-0.99). Virtual abdominal tele-ultrasonography is a promising method in pediatric emergencies.
Purpose
Ultrasonographic quantitative measurements enable characterizing the stiffness and viscosity of liver parenchyma. Normal Shear Wave Elastography (SWE) values have been reported in adults and ...children. The Attenuation Imaging (ATI) coefficient is a measure of local sound energy loss thought to reflect steatosis in adults. The aim of our study was to provide normal SWE and ATI liver values in healthy children.
Methods
A prospective monocentric study was conducted recruiting 86 children (45 boys and 41 girls) from a single University Hospital between January 2019 and June 2020, having a clinically indicated ultrasound examination, without a known or documented history of liver disease. Examinations were performed using an Aplio i800 (Canon Medical Systems) ultrasound system with an i8CX1 transducer. SWE measurements were obtained using a color map showing an automated measurement area grid overlay. ATI coefficients were generated automatically for each region of interest in the right liver.
Results
Overall median age for the pediatric population was 106 months (1–180 months; SD 49 months). Children were normal weighted. Liver SWE was available for all children. The median liver SWE was 4.6 kPa 3.3–6.6. ATI yielded valid measurements in 77 patients. The median ATI coefficient was 0.65 0.5–0.81 dB/cm/MHz. No impact of age, sex, weight and Body Mass Index was observed.
Conclusion
SWE and ATI liver values were provided in healthy children. The normative quantitative data might be useful to characterize liver parenchyma in children better.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
•Acute kidney injury (AKI) occurred in 52.7% of patients with infective endocarditis.•Staphylococcus aureus was the most common species and was associated with AKI.•An infectious disease consultation ...appeared to be a protective factor for AKI.•Exploration of AKI needs to be systematic to conclude on its aetiologies.•Among the 69% patients who survived at one year, 32% had chronic kidney disease.
The incidence of acute kidney injury (AKI) in infective endocarditis (IE), its risk factors and consequences on patient and renal survival remain debated.
Patients hospitalized for a first episode of IE (possible or definite according to modified Duke criteria) between 2013 and 2016 were included. The primary endpoint was to determine risk factors for early AKI (E-AKI) during the first week of management of IE.
A total of 276 patients were included: 220 (79.7%) had definite IE and 56 (20.3%) had possible IE. E-AKI occurred in 150 patients (53%). IE due to Staphylococcus aureus (OR 3.41; 95% CI 1.83–6.39; p<0.01), history of diabetes (OR 2.34; 95% CI 1.25–4.37; p<0.01), peripheral arterial disease (OR 2.59; 95% CI 1.07–6.23; p<0.05), immunological manifestations (OR 3.11; 95% CI 1.31–7.39; p=0.01), and use of norepinephrine (OR 3.44; 95% CI 1.72–7.02; p<0.01) were associated with E-AKI. In subgroup analysis, infectious disease consultation was associated with a lower risk of AKI at day 7 (OR 0.41; 95% CI 0.16–0.88; p=0.04). E-AKI was associated with 1-year mortality (OR 1.65; 95% CI 1.03–2.64; p=0.04) and chronic kidney disease progression (OR 2.23; 95% CI 1.30–3.82; p<0.01).
E-AKI is common in IE and often associated with non-modifiable variables. Multidisciplinary management should be mandatory, and awareness of AKI diagnosis and etiological explorations should be raised.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cerebrovascular disease (CVD) is consistently associated with late-life depression but poorly documented in midlife depression. It can be hypothesized that the relatively low sensitivity of ...conventional neuroimaging techniques does not allow the detection of subtle CVD in midlife depression. We used tissue pulsatility imaging (TPI), a novel ultrasound (US) neuroimaging technique that has demonstrated good sensitivity to detect changes in the pulsatility of small brain volumes, to identify early and subtle changes in brain vascular function in midlife depression. We compared the maximum and mean brain tissue pulsatility (MaxBTP and MeanBTP), as identified by TPI, between three groups of middle-aged females matched for age: patients with depression (n=25), patients with remitted depression (n=24) and community controls (n=25). MRI arterial spin labeling, white matter hyperintensities (WMHs) and transcranial doppler (TCD) were used as control conventional markers for CVD. We found no difference in the MRI and TCD measures among the three groups. In contrast, depressive patients showed an increased BTP related to the mean global brain pulsatility (MeanBTP) and no change related to large vessels (MaxBTP) in comparison with the remitted and control groups. US neuroimaging is a highly accurate method to detect brain pulsatility changes related to cerebrovascular functioning, and TPI identified an increased BTP in midlife depressed patients, suggesting early and subtle vascular impairments in this population at risk for CVD such as stroke or WMHs. Because high pulsatility could represent prodromal cerebrovascular changes that damage the brain over time, this paper provides a potential target for blocking the progression of CVD.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Recent evidence suggests that biomechanical parameters of the brain, such as Brain Tissue Pulsatility (BTP), could be involved in emotional reactivity. However, no study has investigated the impact ...of an emotional task on BTP. We used the ultrasound method of Tissue Pulsatility Imaging (TPI) to assess changes in BTP to exciting and relaxing classical music, in a musical perception task, as a validated paradigm to assess emotional reactivity.
25 healthy volunteers were exposed via earphones to four 5-minute musical excerpts (two exciting and two relaxing musical excerpts) presented in a randomized order and intersected by 5 silence periods. Measures of BTP, Heart Rate (HR) and Skin Conductance (SC) were collected during the entire task.
The BTP significantly decreased with relaxing music compared to silence, and especially with the excerpt ‘Entrance of the Shades’ by Minkus. The HR and SC, but not Heart Rate Variability, were also decreased with relaxing music. We found no significant effect of exciting music.
We report, for the first time, that classical relaxing music decreases the amplitude of the brain pulsatile movements related to cerebral blood flow and mechanical properties of the brain parenchyma, which provides further evidence of the involvement of BTP in emotional reactivity. In addition, we validate the use of TPI as a non-invasive, portable and low cost tool for studies in psychophysiology, with the potential to be implemented as a biomarker in musicotherapy trials notably.
•We investigated changes in Brain Tissue Pulsatility with exciting and relaxing music.•Brain Tissue Pulsatility decreased with relaxing music compared to silence.•Parameters of the Autonomous Nervous System also decreased with relaxing music.•Tissue Pulsatility Imaging could constitute a biomarker of brain reactivity to music.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background
Nonalcoholic fatty liver disease (NAFLD) refers to a large spectrum of liver disorders and is the most common cause of metabolic liver disease. The current gold standard for diagnosing ...NAFLD is liver biopsy, which can lead to severe complications.
Purpose
Among the noninvasive diagnostic options, we chose to use a FibroScan and developed an algorithm applying the Voigt rheological model to assess the viscoelastic properties of the liver and evaluate its performance for the diagnosis of steatosis.
Methods
Twenty‐two healthy volunteers and 20 patients with steatosis were included. For each subject, we used a modified FibroScan, whose data had been processed by our algorithm to separate the two viscoelastic components, stiffness μ, and viscosity η. The liver elasticity μFibroscan measured by the FibroScan was also recorded. Mann–Whitney tests and receiver operating characteristics (ROCs) curve analyses were performed to compare the parameters between the two groups, and Pearson's correlation coefficients were used to assess the correlations between the parameters.
Results
We found a good correlation between η and μFibroscan (r = 0.75), and poor correlations between μ and both η and μFibroscan (r = 0.33 and r = 0.03, respectively). We also showed that η and μFibroscan were higher in patients with steatosis compared to healthy volunteers, with area under the ROCs (AUROC) curve at 0.814 and 0.891, respectively. Conversely, μ was not different between the two groups (AUROC = 0.557).
Conclusions
Our novel method successfully separated the two viscoelastic properties of the liver, of which the parameter η is a sensitive indicator for steatosis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Purpose
Despite their functional importance, the infraspinatus (ISP) and teres minor (TM) muscles have been little investigated. This study aimed to describe the macroscopic morphology, innervation, ...and inter-relations of the ISP and TM muscles.
Methods
Forty fresh cadaver dissections and histologic analysis were performed. Three groups of specimens were distinguished according to the rotator cuff tendon status: (1) intact rotator cuff; (2) supraspinatus tendon tears with intact ISP tendon; and (3) both supraspinatus and ISP tendons torn. Muscle fiber organization and muscle and tendon length were recorded. ISP and TM innervation and fiber structure were studied.
Results
ISP muscles were composed of three groups of fiber organized in two planes: two superficial groups, with mean pennation angles of, respectively, 27° ± 4° and 23° ± 3° with respect to the axis of the central tendon of the underlying group. TMs were thick fusiform muscles showing a parallel organization; 26 specimens (67 %) had aponeuroses isolating the TM, with a mean length of 5.2 ± 2.7 cm. Rotator cuff lesions were associated with relatively greater ISP tendon than muscle length. Innervation of the ISP muscle comprised 2–4 main branches from the suprascapular nerve and that of the TM 1 branch from the axillary nerve.
Conclusion
ISP muscle body morphology derives from three groups of fibers in two planes. The TM has a parallel organization. Several nerve branches innervate the ISP muscle, whereas only one supplies the TM. The limits between the two muscles bodies consist of an aponeurotic fascia in two-thirds of cases.
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