14 research outputs found
Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey
Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
Développement et altération du cerveau: approche par IRM de diffusion et tractographie
Regional differences in interhemispheric structural fibers in healthy, term infants
Using fiber tracking we investigated the early interhemispheric to cortical development by segmenting the corpus callosum (CC) in five substructures, genu, rostrum, body, isthmus, and splenium, and to examine gender differences in healthy, term neonates. Twenty neonates (11 boys aged 39 ± 2 days, nine girls aged 39 ± 1 days) were scanned in natural sleep with diffusion tensor imging and 35 gradient directions. Fiber tracking was performed using the FACT algorithm. The CC was segments in five substructures on midsagittal imaging. The fiber axial and radial diffusion were measured along with apparent diffusion coefficient and fractional anisotropy. Volume measures were performed for each of these substructures using high-resolution isotropic 3D T1-weighted images. Radial and mean diffusivity in all measured interhemispheric connections were significantly higher in male newborn infants than in female. Second, a gender-dependent regional difference of the measured interhemispheric connections exists. There was no volume difference between boys and girls in any of the five studied sudsubstructures. In addition there was no association between macrostructural and microstructural differences either in boys or girls. The cytoarchitecture and the integrity of the interhemispheric fibers is more developed in female infants in all subdivisions of the CC, except for the isthmus. This might result from a larger axonal diameter, highly packed fibers, or more well-developed myelin sheath. © 2016 Wiley Periodicals, Inc
Early assessment of lateralization and sex influences on the microstructure of the white matter corticospinal tract in healthy term neonates
We assessed the sex and the lateralization differences in the corticospinal tract (CST) during the early postnatal period. Twenty-five healthy term neonates (13 girls, aged 39.2 ± 1.2 weeks, and 12 boys aged 38.6 ± 3.0 weeks) underwent Diffusion Tensor Imaging (DTI). Fiber tracking was performed to extract bilaterally the CST pathways and to quantify the parallel (E ) and perpendicular (E ) diffusions, the apparent diffusion coefficient (ADC), and fractional anisotropy (FA). The measurements were performed on the entire CST fibers and on four segments: base of the pons (CST-Po), cerebral peduncles (CST-CP), posterior limb of the internal capsule (CST-PLIC), and corona-radiata (CST-CR). Significantly higher E , lower E and higher FA in the right compared to the left were noted in the CST-PLIC of the girls. Significantly lower E and lower ADC with higher FA in the right compared to left were observed in the CST-CP of the boys. Moreover, the CST-PLIC of the boys had significantly higher E in the right compared to the left. There was a significant increase in left CST E of boys when compared with girls. Girls had a significantly lower E , lower E and, lower ADC in the left CST-CP compared with boys. In addition, girls had a significantly lower E and higher FA in the right CST-PLIC compared with boys. Sex differences and lateralization in structure-based segments of the CST were found in healthy term infants during early postnatal period. These findings are vital to understanding motor development of healthy term born neonates to better interpret newborn infants with abnormal neurodevelopment
A Phase-Contrast MRI Study to Investigate the Interaction of the CSF Dynamic with the Intracranial CSF Distribution
PURPOSES: Cine PC-MRI has shown that CSF oscillations increase with age, while the ratio between the CSF Oscillation in the aqueduct and the spinal canal is constant. Our aim was to test whether the CSF hydrodynamic can bring complementary information to study pediatric population with an increase of the CSF volume.
Material and Method: Forty three patients, newborns and children (mean age: 31 ± 32 months; 5 days - 111 months) with an intracranial CSF volume increase (ventricular or/and subarachnoid spaces) underwent a morphological MRI along with cine PC-MRI to quantify CSF oscillations. We defined a ratio of the ventricular area to that of the intracranial subarachnoid spaces (CSFratio). We also determined an index called CSFdynamic, which equals the CSF aqueduct stroke volume (SVAq) divided by the cervical stroke volume (SVC2C3) at the level C2C3 in the spine.
RESULTS: Twenty-three patients presented only ventricular dilatation: CSFdynamic = 20 ± 25; CSFratio: 120 ± 151; with no significant correlation, (rs = 0.152, p = 0.48). Sixteen patients presented both ventricular and subarachnoid space dilations: CSFdynamic = 18 ± 17; CSFratio = 1.67 ± 0.81; with significant positive correlation (rs =
0.5911 p = 0.016).
CONCLUSIONS: In pediatric population, the absence of correlation between the dynamic of the CSF and its volume shows that the CSF oscillation does not result only of the size of the ventricles and/or the subarachnoid spaces. The CSF oscillations bring complementary information concerning the active aspect of the CSF
Fold-Over Oversampling Effects in the Measurements of Cerebral Cerebrospinal Fluid and Blood Flows with 2D Cine Phase-Contrast MRI
This prospective study investigated the effects of fold-over oversampling on phase-offset background errors with 2D-Cine phase contrast (Cine-PC) magnetic resonance imaging (MRI). It was performed on brain MRI and compared to conventional Full-field of view FOV coverage and it was tested with two different velocity encoding (Venc) values. We chose Venc = 100 mm/s to encode cerebrospinal fluid (CSF) flows in the aqueduct and 600 mm/s to encode blood flow in the carotid artery. Cine-PC was carried out on 10 healthy adult volunteers followed simultaneously by an acquisition on static agar-gel phantom to measure the phase-offset background errors. Pixel-wise correction of both the CSF and the blood flows was calculated through 32 points of the cardiac-cycle. We compared the velocity-to-noise ratio, the section area, the absolute and the corrected velocity (peak; mean and minimum), the net flow, and the stroke volume before and after correction. We performed the statistical T-test to compare Full-FOV and fold-over and Bland–Altman plots to analyze their differences. Our results showed that following phase-offset error correction, the blood stroke-volume was significantly higher with Full-FOV compared to fold-over. We observed a significantly higher CSF mean velocity and net flow values in the fold-over option. Compared to Full-FOV, fold-over provides a significantly larger section area and significantly lower peak velocity-offset in the aqueduct. No significant difference between the two coverages was reported before and after phase-offset in blood flow measurements. In conclusion, fold-over oversampling can be chosen as an alternative to increase spatial resolution and accurate cerebral flow quantification in Cine-PC
An innovative approach to investigate the dynamics of the cerebrospinal fluid in the prepontine cistern: A feasibility study using spatial saturation-prepared cine PC-MRI
Purposes: Accurate measurements of the cerebrospinal fluid that flows through the prepontine cistern (PPC) are challenging due to artefacts originating from basilar artery blood flow. We aim to accurately quantify cerebrospinal fluid (CSF) flow and stroke volume in the PPC, which is essential before endoscopic third ventriculostomy.
Materials and methods: We developed a new PC-MRI sequence prepared with Hadamard saturation bands to accurately quantify CSF flow in the PPC by suppressing the blood signal in the surrounding vessels. In total, 28 adult hydrocephalic patients (age 59 ± 20 years) were scanned using conventional PC-MRI and our developed sequence. CSF was separately extracted from the PPC and the foramen of Magendie, and flow (min and max) and stroke volume were quantified.
Results: Our modifications result in a complete deletion of signal from flowing blood, resulting in significantly reduced CSF stroke volume (Conv = 446 ± 113 mm3, Dev = 390 ± 119 mm3, p = 0.006) and flow, both minimum (Conv = −1630 ± 486 mm3/s, Dev = −1430 ± 406 mm3/s, p = 0.005) and maximum (Conv = 2384 ± 657 mm3/s, Dev = 1971 ± 62 mm3/s, p = 0.002) compared with the conventional sequence, whereas no change in the area of interest was noted (Conv = 236 ± 65 mm2, Dev = 249 ± 75 mm2, p = 0.21).
Conclusions: Accurate and reproducible CSF flow and stroke volume measurements in the PPC can be achieved with sat-band prepared cine PC-MRI
Total Cerebrovascular Blood Flow and Whole Brain Perfusion in Children Sedated Using Propofol With or Without Ketamine at Induction: An Investigation With 2D-Cine PC and ASL
BACKGROUND
Multiple sedation regimes may be used to facilitate pediatric MRI scans. These regimes might affect cerebral blood flow and hemodynamics to varying degrees, particularly in children who may be vulnerable to anesthetic side effects.
PURPOSE
To compare the effects of propofol monosedation solely (Pm group) vs. a combination of propofol and ketamine (KP group) on brain hemodynamics and perfusion