25 research outputs found
Utility of enhanced CT for patients with suspected uncomplicated renal colic and no acute findings on non-enhanced CT
AIM: To evaluate the utility of contrast-enhanced computed tomography (CECT) for patients with suspected uncomplicated renal colic (URC) and no abnormalities on non-enhanced computed tomography (NECT).
MATERIALS AND METHODS: The hospital institutional review board and ethics committee approved this retrospective study with a waiver of informed consent. Between January 2016 and April 2017, all consecutive adult patients who consulted at the adult Emergency Department (ED) with suspected URC and who had undergone both NECT and CECT were included retrospectively. The primary endpoint was prevalence of CECT-only diagnosis without acute findings on NECT. The risk factors for an acute finding were identified by logistic regression analysis.
RESULTS: Among 126 patients with suspected URC, 12 were excluded. Among the 76 patients with no acute findings on NECT, CECT led to find acute lesions in 14/76 (18%) cases, but only 2/76 (3%) resulted in a change of management. Predictive factors of abnormal finding on CECT were: low renal clearance and high leukocyte count with OR 0.96 (95% confidence interval [CI]: 0.93-0.99), p=0.0189 and OR 5.79 (95% CI: 1.55-21.64), p=0.0091, respectively.
CONCLUSIONS: In most cases, NECT is sufficient for screening patients with suspected URC. If leucocytosis and low renal function are present, stronger consideration may be given to CECT
Whole-Body CT after Motor Vehicle Crash: No Benefit after High-Energy Impact and with Normal Physical Examination
Background Debate continues about the risks and benefits of systematic whole-body CT when no injury is clinically suspected. Risks of whole-body CT include high radiation exposure and iodine contrast agent, but its effectiveness in reducing mortality in low-risk motor vehicle crashes is unclear. Purpose To assess unsuspected injuries revealed at whole-body CT in patients following motor vehicle crash (MVC) meeting only kinetic elements of the Vittel criteria for the severity of trauma, with no evidence of trunk injury and a Glasgow Coma Scale score of 15. Materials and Methods This retrospective study included all consecutive adult patients who consulted an emergency department of a level 1 trauma center between August 2016 and July 2017 if they underwent whole-body CT for one or more kinetic elements of the Vittel criteria, had a normal examination of the trunk, and had a Glasgow Coma Scale score of 15. Data of the MVC mechanism and physical and biologic examinations were collected, as well as patient treatment data after whole-body CT. Whole-body CT examinations were read by two double-blinded readers to help detect unsuspected injuries. Results Ninety-three patients were included; 72 were men with a mean age of 30.8 years ± 12.0 (standard deviation). Sixty-nine patients were occupants of a car. Seventeen patients were hit by a car while on motorbikes, three while on bicycles, and four as pedestrians. Unsuspected injuries were depicted at 11 whole-body CT examinations: eight lung contusions, one acetabular fracture, one sternal fracture, and one adrenal hematoma. None of these injuries required a specific treatment. One patient with lung contusion of more than 30% of lung volume was followed without requiring further treatment. Conclusion In this population, whole-body CT did not lead to any change in patient treatment. These results suggest whole-body CT should not be systematically performed when no evidence of trunk injury is observed in patients following motor vehicle crash meeting only kinetic elements of Vittel criteria. © RSNA, 2019 See also the editorial by Munera and Durso in this issue
Suspicious liver nodule in chronic liver disease: Usefulness of a second biopsy
PURPOSE: To assess the usefulness of a second biopsy when the first one was inconclusive in patients with a liver nodule found during the follow-up for chronic liver disease.
MATERIALS AND METHODS: Among 381 patients (544 nodules) included in a prospective study designed to evaluate the accuracy of imaging for the diagnosis of small hepatocellular carcinoma (HCC) in chronic liver disease, 254 nodules were biopsied. The following histological results were considered as conclusive: HCC, dysplastic or regenerative nodule, and other identified tumors (benign or malignant). For nodules with inconclusive results (e.g. fibrosis or no definite focal lesion), a second biopsy was suggested, but was not mandatory.
RESULTS: A total of 242 patients (194 men, 48 women; mean age, 61.9±9.5 [SD]; range: 40.2-89.0years) with 254 nodules underwent a first biopsy. Mean nodule diameter was 19.2±5.4mm (range: 10-33mm). The first biopsy was conclusive in 189/254 nodules (74.4%): 157 HCCs (83.1%), 11 regenerative nodules (5.8%), 10 dysplastic nodules (5.3%), 3 cholangiocarcinomas (1.6%), and 8 other tumors (4.2%). Among the 65 nodules for which the first biopsy was inconclusive, a second biopsy was performed for 17 nodules in 16 patients within 6 months of the first one. It was conclusive in 13/17 nodules (76.5%): 10 HCCs (76.9%), 2 dysplastic nodules (15.4%), and 1 other tumor (7.7%). In 4/17 nodules (23.5%), no definitive diagnosis could be provided.
CONCLUSION: The diagnostic yield of a second biopsy of a suspicious lesion suggestive of HCC in chronic liver disease is not decreased compared to the first one. Repeated biopsy after a first negative one could be an alternative option to the follow-up of patients with chronic liver disease
Doppler ultrasonography devices, including elastography, allow for accurate diagnosis of severe liver fibrosis
OBJECTIVES: Advanced chronic liver disease is frequent yet largely underdiagnosed. Doppler-US is a common examination and we recently identified three simple Doppler-US signs associated with severe liver fibrosis. Recent Doppler-US devices include elastography modules, allowing for liver stiffness measurement (LSM). Our aim was to assess whether the use of elastography following positive simple Doppler-US signs improves the detection of severe liver fibrosis in a single Doppler-US examination.
METHODS: 514 patients with chronic liver disease who consecutively underwent percutaneous liver biopsy were included in the study. All patients had a Doppler-US examination and LSM with Virtual Touch Quantification (VTQ) on the same day as a liver biopsy. A subset of 326 patients also had LSM with 2D shear wave elastography (SSI). Severe fibrosis was defined as Metavir F ≥ 3 on liver biopsy.
RESULTS: Multivariate analysis confirmed our three simple Doppler-US signs (liver surface irregularity, splenomegaly ≥110 mm, and demodulation of hepatic veins) as independently associated with severe fibrosis. The presence of at least one of these three signs showed 85.6% sensitivity and 36.1% specificity for the diagnosis of severe liver fibrosis. Using VTQ (≥1.59 m/s) where there was a positive Doppler-US sign increased the specificity to 80.8%, at the cost of a decrease in sensitivity (73.7%). Similar results were obtained with SSI (≥9.5 kPa), with 73.3% specificity and 81.5% sensitivity.
CONCLUSION: Elastography improves the accuracy of Doppler-US in the detection of severe fibrosis. This two-step procedure will help radiologists to accurately identify patients who need to be referred to specialist hepatologists during routine Doppler-US examinations
Direct Reprogramming of Mouse Fibroblasts into Functional Skeletal Muscle Progenitors
Skeletal muscle harbors quiescent stem cells termed satellite cells and proliferative progenitors termed myoblasts, which play pivotal roles during muscle regeneration. However, current technology does not allow permanent capture of these cell populations in vitro. Here, we show that ectopic expression of the myogenic transcription factor MyoD, combined with exposure to small molecules, reprograms mouse fibroblasts into expandable induced myogenic progenitor cells (iMPCs). iMPCs express key skeletal muscle stem and progenitor cell markers including Pax7 and Myf5 and give rise to dystrophin-expressing myofibers upon transplantation in vivo. Notably, a subset of transplanted iMPCs maintain Pax7 expression and sustain serial regenerative responses. Similar to satellite cells, iMPCs originate from Pax7+ cells and require Pax7 itself for maintenance. Finally, we show that myogenic progenitor cell lines can be established from muscle tissue following small-molecule exposure alone. This study thus reports on a robust approach to derive expandable myogenic stem/progenitor-like cells from multiple cell types
Direct Reprogramming of Mouse Fibroblasts into Functional Skeletal Muscle Progenitors
Summary Skeletal muscle harbors quiescent stem cells termed satellite cells and proliferative progenitors termed myoblasts, which play pivotal roles during muscle regeneration. However, current technology does not allow permanent capture of these cell populations in vitro. Here, we show that ectopic expression of the myogenic transcription factor MyoD, combined with exposure to small molecules, reprograms mouse fibroblasts into expandable induced myogenic progenitor cells (iMPCs). iMPCs express key skeletal muscle stem and progenitor cell markers including Pax7 and Myf5 and give rise to dystrophin-expressing myofibers upon transplantation in vivo. Notably, a subset of transplanted iMPCs maintain Pax7 expression and sustain serial regenerative responses. Similar to satellite cells, iMPCs originate from Pax7+ cells and require Pax7 itself for maintenance. Finally, we show that myogenic progenitor cell lines can be established from muscle tissue following small-molecule exposure alone. This study thus reports on a robust approach to derive expandable myogenic stem/progenitor-like cells from multiple cell types
The Effects of Individual Augmentation (IA) on Navy junior officer retention
In 2000, the Navy started the Individual Augmentation (IA) deployment program. IA deployment provides a tool for military leaders to designate and assign specific individuals, not forces, to fill temporary duty jobs outlined by combatant commanders in support of National Command Authority (NCA) directed operations. IA is one of the Navy's' means of contributing to the Global War on Terror (GWOT) and Operation Iraqi Freedom (OIF). This thesis uses standard statistical modeling techniques to quantify the effects of IA deployments on Navy junior officer retention. Using these models we found that the odds of retention for junior officers who went on IA deployments were statistically significantly higher than for those officers that did not. This is an important result because Navy leaders have said that IA deployments will continue in the future. Officers are the foundation of the Navy command and leadership structure; therefore, it is important to understand the effects these deployments have on their retention.http://archive.org/details/theeffectsofindi109454195US Navy (USN) author.Approved for public release; distribution is unlimited
Surgical management of adhesive small bowel obstruction: Is it still mandatory to wait? – An update
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Single-phase flow in a pulsed column: Particle Image Velocimetry validation of a CFD based model
International audienceThe pulsed column is a widely used technology for liquid-liquid extraction processes in various industries. A thorough understanding of the biphasic flow in the column is essential to achieve process optimization and design. This paper is dedicated to the modelling of the single-phase flow which is strongly influencing the transport, breakage and coalescence of droplets in the apparatus. In this aim, a Computational Fluid Dynamics (CFD) model was developed for the simulation of a disc and doughnut pulsed column. To discuss the relevance of the RANS-based CFD model, the simulation results have been compared to Particle Image Velocimetry (Ply) measurements synchronized on the pulsation period. Since the behaviour of the dispersed phase is strongly dependent on the turbulent properties of the flow, such as eddies size and dissipation rate, the discussion is focussed on turbulent quantities. In this aim, 3D simulations were first carried out and compared to 2D axisymmetric ones. Then, different numerical schemes and turbulence models were compared to experimental data to choose the model offering the most accurate modelling of the single-phase flow