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2.
《Cancer radiothérapie》2022,26(8):1008-1015
PurposeDeep learning (DL) techniques are widely used in medical imaging and in particular for segmentation. Indeed, manual segmentation of organs at risk (OARs) is time-consuming and suffers from inter- and intra-observer segmentation variability. Image segmentation using DL has given very promising results. In this work, we present and compare the results of segmentation of OARs and a clinical target volume (CTV) in thoracic CT images using three DL models.Materials and methodsWe used CT images of 52 patients with breast cancer from a public dataset. Automatic segmentation of the lungs, the heart and a CTV was performed using three models based on the U-Net architecture. Three metrics were used to quantify and compare the segmentation results obtained with these models: the Dice similarity coefficient (DSC), the Jaccard coefficient (J) and the Hausdorff distance (HD).ResultsThe obtained values of DSC, J and HD were presented for each segmented organ and for the three models. Examples of automatic segmentation were presented and compared to the corresponding ground truth delineations. Our values were also compared to recent results obtained by other authors.ConclusionThe performance of three DL models was evaluated for the delineation of the lungs, the heart and a CTV. This study showed clearly that these 2D models based on the U-Net architecture can be used to delineate organs in CT images with a good performance compared to other models. Generally, the three models present similar performances. Using a dataset with more CT images, the three models should give better results. 相似文献
3.
Bioimpedance as a measure of fluids in patients with septic shock. A prospective observational study
Janne Meisner Madsen Theis S. Itenov Ellen Bjerre Koch Morten H. Bestle 《Acta anaesthesiologica Scandinavica》2023,67(3):319-328
Background
Septic shock is often treated with aggressive fluid resuscitation leading to profound fluid overload. The assessment of fluid status relies on suboptimal measures making treatment difficult. Bioelectrical impedance analysis is an alternative but the validity is unclear. The aim of this study was to determine the validity of bioelectrical impedance analysis for fluid measures in patients with septic shock.Methods
Single-center, prospective observational cohort study. We included adult ICU patients with septic shock. We evaluated the agreement between measures on the left and right side of the patient and measures 1 h apart by two bioelectrical impedance devices. Results are presented as Bland Altman plots with 95% Limits of Agreements (LoA) and as correlations between bioelectrical impedance analysis results and clinical markers of fluids.Results
Forty-nine patients were included. The agreement between measures on the left and the right side of the patient and after 1 h was overall without bias, but with wide LoA's. Fluid overload 1 h apart showed the most narrow 95% LoA (−2.4–2.9 L). The same wide limits of agreements were observed when comparing devices. For example, total body water with 95% LoA of −14.8 –16.7 L. Correlations between bioelectrical impedance analysis and clinical measures were low but statistically significant.Conclusions
In patients with septic shock bioelectrical impedance analysis had no systematic errors or bias, but wide limits of agreement, indicating that the devices have a large and uncorrectable random error. Fluid status by bioelectrical impedance analysis is not sufficiently accurate to guide treatment in this group of patients. 相似文献4.
5.
《Vaccine》2022,40(15):2274-2281
We evaluated compliance to the ACIP pneumococcal vaccination recommendations issued in 2014 for adults aged ≥ 65 years and in 2012 for adults with high-risk (HR) conditions. The MarketScan® Commercial and Medicare Supplemental databases (January 2007-June 2019) were used to identify the cohorts of interest. Analyses for adults aged ≥ 65 years were adjusted to account for missing vaccination history. Two HR cohorts were identified. The HR1 cohort included patients with immunocompromising conditions, functional or anatomic asplenia, cerebrospinal fluid leak, or cochlear implant. The HR2 cohort included patients with chronic heart, lung, or liver disease; diabetes mellitus; alcoholism; cirrhosis; or cigarette smoking. Full compliance for those aged ≥ 65 years or in the HR1 cohort was defined as receipt of PCV13 and PPSV23, and partial compliance was defined as receipt of PCV13 or PPSV23. For those in the HR2 cohort, full compliance was defined as receipt of PPSV23. Annual compliance rates were estimated using the Kaplan–Meier method.Among those aged ≥ 65 years, partial compliance at 4 years post index was 53% and full compliance was 17% in adjusted analyses. In subjects ≥ 65 years receiving the first vaccination, 42% received the second vaccination by year 4. For the HR1 cohort, partial compliance was 19% and full compliance was 5% at 6 years post index date. For the HR2 cohort, full compliance was 20% at 6 years, with the highest rate in patients with diabetes (27%) and the lowest rate in patients with alcoholism (8%).Additional efforts are needed to maximize compliance to the ACIP pneumococcal vaccine recommendations among adults ≥ 65 years of age and adults with HR conditions including streamlined recommendations and single-dose vaccines. These efforts may subsequently reduce the incidence and burden of pneumococcal disease. 相似文献
6.
《Neuro-Chirurgie》2023,69(5):101478
ObjectivePituitary abscess is an often misdiagnosed, rare clinical disorder. To improve diagnostic accuracy and the efficacy of surgical and antibiotic therapy for patients with pituitary abscess, herein, we retrospectively reviewed 15 patients who presented with pituitary abscesses from 2005 to 2022.DesignRetrospective study.PatientsFifteen patients underwent transsphenoidal surgery and received antibiotic treatment.MeasurementsComplete details regarding medical history, clinical manifestations, laboratory examinations, imaging studies, and treatment strategies were obtained for all patients.ResultsMost patients presented with hypopituitarism and headaches, while some presented with fever, visual disturbances, and diabetes insipidus (DI). Abscesses showed significant annular enhancement post gadolinium injection. In most patients, pituitary abscess can be cured via microscopic or endoscopic drainage of the abscess followed by antibiotic treatment. Complete cure of pituitary abscess was observed in nine patients, with six cases of prolonged hypopituitarism and only one case of recurrence. Long-term hormone replacement therapy was effective in the postoperative management of hypopituitarism.ConclusionsThe typical manifestations of pituitary abscess include hypopituitarism and headaches; the presence of an enhanced ring at the edge of the mass on contrast-enhanced magnetic resonance images (MRI) is highly suggestive of pituitary abscess. We recommend antibiotic treatment for 4–6 weeks postoperatively, based on the results of bacterial cultures or metagenomic next-generation sequencing (mNGS). 相似文献
7.
目的:对食管胃结合部腺癌近端胃切除术(PG)人工三角瓣成形后残胃食糜进行流体动力学数值模拟,并计算不同性质胃内食糜的流动特征。方法:构建常规PG和人工三角瓣成形术术后胃仿真模型,运用Fluent软件对不同粘度胃内食糜反流问题进行数值模拟。结果:站立位姿态时,相对常规PG方案,人工三角瓣成形手术方案表现出较好的抗反流作用;卧位姿态时,当胃内食糜粘度大于0.145 2 Pa[?s,且胃内食糜不超过人工三角瓣情况下,人工三角瓣成形抗反流手术表现出较好的抗反流效果;人工三角瓣抗反流成形手术方案数值模拟结果与临床上患者表现一致。结论:本研究仿真分析为人工三角瓣成形抗反流手术方案的有效性机理分析、临床患者术后饮食及手术方案的进一步改进提供理论及数值依据。
【关键词】食管胃结合部腺癌;抗反流;人工三角瓣;计算流体力学 相似文献
8.
Sine Wichmann Martin Schønemann-Lund Anders Perner Theis S. Itenov Theis Lange Christian Gluud Rasmus E. Berthelsen Anne C. Brøchner Jørgen Wiis Morten H. Bestle 《Acta anaesthesiologica Scandinavica》2023,67(4):470-478
Background
Salt and water accumulation leading to fluid overload is associated with increased mortality in intensive care unit (ICU) patients, but diuretics' effects on patient outcomes are uncertain. In this first version of the GODIF trial, we aimed to assess the effects of goal-directed fluid removal with furosemide versus placebo in adult ICU patients with fluid overload.Methods
We conducted a multicentre, randomised, stratified, parallel-group, blinded, placebo-controlled trial in clinically stable, adult ICU patients with at least 5% fluid overload. Participants were randomised to furosemide versus placebo infusion aiming at achieving neutral cumulative fluid balance as soon as possible. The primary outcome was the number of days alive and out of the hospital at 90 days.Results
The trial was terminated after the enrolment of 41 of 1000 participants because clinicians had difficulties using cumulative fluid balance as the only estimate of fluid status (32% of participants had their initially registered cumulative fluid balance adjusted and 29% experienced one or more protocol violations). The baseline cumulative fluid balance was 6956 ml in the furosemide group and 6036 ml in the placebo group; on day three, the cumulative fluid balances were 1927 ml and 5139 ml. The median number of days alive and out of hospital at day 90 was 50 days in the furosemide group versus 45 days in the placebo group (mean difference 1 day, 95% CI -19 to 21, p-value .94).Conclusions
The use of cumulative fluid balance as the only estimate of fluid status appeared too difficult to use in clinical practice. We were unable to provide precise estimates for any outcomes as only 4.1% of the planned sample size was randomised. 相似文献9.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients. 相似文献
10.
《中国现代医生》2020,58(21):78-81
目的 分析7例羊水栓塞的临床诊断与抢救,提供临床诊治羊水栓塞的参考,以提高抢救成功率。方法选取2011年1月~2019年10月于本院住院治疗的7例羊水栓塞的产妇临床资料、救治措施、预后及有无并发症进行回顾性分析。结果 7例羊水栓塞患者中,4例行剖宫产术,3例阴道分娩,经多学科合作积极抢救,4例抢救成功,1例有肺挫裂伤、胸骨、肋骨骨折,其余3例无并发症,1例植物人状态,2例死亡(死于严重的DIC、多器官功能衰竭)。结论 羊水栓塞起病急骤、表现不一、进展快,死亡率高,因此早期识别、积极治疗,多学科合作,必要时及时行子宫切除术,可提高抢救成功率,改善预后、减少并发症的发生。 相似文献